Dimensional Challenges are different from Expert Challenges of Monster Train 1. And I approve this changes.
First. Unlike Expert Challenges, all D-challenges do NOT set to maximum difficulty (covenant rank 10). Most of Expert Challenges were rather frustrating and painful than fun. They were typically require numerous attempts even by real Expert players. And regular players simply suffered in these type of missions.
Second. All D-challenges restricted to specific setup - pair of clans, covenant rank and pyre heart. This makes the difficulty level of the trial more concrete and defined. Also, though there is multiple potential solutions to obstacles, this allows to give more specific recommendations for completing particular mission.
Third. There is sometimes additional modificator - non-standard Pyre Heart with unique functionality to gameplay.

For information organization and convenience, I created categories based on my experience and assessments. I identified three levels of Dimensional Challenges:

"Having Fun" tier with mostly positive modificators and/or real strong ones. You're basically play different game mod for fun and variety. The difficulty is the same or lower than in a regular run.

"Adapt to Distinct playstyle" tier with mutators, which twisting and warping core formula beyond recognition, but not too difficult.

"True Challenge" tier with mostly negative modificators, there you basically required luck to highroll some strong combo to succeed. And, in fact, it may take several attempts to beat them.

*All Challenges were completed by me in the game version #12000 (update 1.1.3)

This is the achievement that is given for completing "Entropic Agony" portal mission, so it's related to dimensiomal challenges. So technically this guide helps in getting this achievement.
"Malicka's Sidekick" is one of the difficult achievements, as it requires actually knowing how to play efficiently. Though difficult is the wrong word in this context. It's a mix of strategy development, probabilities, understanding of value and planning ahead. That's the skill required, it's not some kind of precision based execution.

I would like to give some general advice that I hope will help not only beginners, but also more experienced players as well.

Try to keep your deck thin. Don't add cards unless you're sure you'll use them. Option to pass cards at draft is super valuable and important in deckbuilding games as your deck needs to be balanced and properly builded. Another valuable option is card removal in shops. Your starter cards may become almost useless or obsolete by the mid of the game and It's better to remove them.

In the vast majority of cases taking unit upgrades as soon as possible is priority, as they provide a greater return on investment at early levels. It is also better to first look at what upgrades are available from the merchant of steel, and only then choose a fighter taking this information into account.

Duplicating upgraded units is usually wonderful. Removing units isn't as important as the first game, as deployment phase lessens the negative impact of Stewards. Though Spear Steward is worst unit in the game and only useful in couple of early fights, so removing them is often a priority, especially if there is no capacity to place them.

"Holystone"
"Pyre Health" spell upgrade is almost worthless at the moment. Well, not everything is so categorical, it's just always (except rare cases) better to spend gold on something more useful, because it's less bang for your buck. And that's the gamedesign issue, because no one except newbie players uses this function. I see only one use case for Holystone, when there is extra gold that simply has nowhere to spend.



Don't be afraid to push the restart turn/battle buttons, as these aren't punished. These are tools that allow you to beat almost every fight if you've constructed rather competently.

Most relics can be slightly overrated. Sorry, I know Monster Train calls them artifacts, but I prefer to call them relics. Don't force a path just to get relics, as they're mostly not as impactful as they are in other deckbuiling games. Of course, there are exceptions which I will discuss below.

"Ancient Pyretap"
This is a super strong relic, I wouldn't even be surprised if it will be nerfed consequently. It provide essentially limitless energy as long as you are willing to sacrifice Pyre health. This allows you to play expensive 3+ spells and deploy expensive units in the deployment phase. It is very important to play key cards, regardless of the energy. Health is a resource that often sits idle, also Pyre Health nodes can sometimes be passable and worthless, because you're at full health. So if you managed to get this relic, you're on a way to win!


"Shadow's Sheath"
This is a mighty Build-forming relic, which gives Stealth to friendly unit on Slay. It's very good with sweeper units (Pyre of Savagery is a great addition to this combo as well). Also Quick upgrade or ability on a sweeper and this relic is desirable combo. It trivialises potential hazards like backline sweeping enemies, healers, buffers, debuffers, etc. as these are often glassy. If you have the opportunity to get a unit with sweep&quick while owning "Shadow's Sheath", it will carry you to victory.
Stealth can hide your tanks and make backline vulnerable though. So "Shadow's Sheath" should be used with caution and smartly.


"Emot Tome"
"Create an Ephemeral copy of the first spell you play each turn". This is another Build-forming relic and tome can be ridiculous with some improved spells. This relic works great even if you don't focus on magic. As there are almost always important spells that you willing to play twice.

Well, I don't think anyone will have any difficulties here. "Enchanted Armory" (equipment cards cost 0 energy) is a HUGE advantage. Just pick up and combine two equipment cards in one and make it Deployable - result may wary from "powerful" to "absolutely broken". Also Banished is one of the best clans and Fel's permanent "Shift" path is quite insane.
I guess, enjoy total destruction of Seraph.

In this one enemies enter with double Damage Shield, which seems scary. But "Highly Reactive" (Triggers activate twice on your units) and "Duality" (Double stack of all statuses) are very strong mutators and this is a Major compensation. The task here is taking advantage of the double status effects better than enemy units can.
Choosing trigger-themed cards and relics is especially beneficial due to the "Highly Reactive" mod. For example, puny Rage-Imp gives 20 Rage status for all units! I hope I don't need to explain it any further...
Awoken clan have good accessible sweepers to remove Damage Shields from enemies on the floor, there is other solutions to this issue like multistrike or AoE spells. Don't be too greedy with "Mark of Invasion" trials, when enemy units appear on each floor, and you'll be fine.
I was lucky and get demon's stick of multistrike from start while doing this mission, but even without that the mission isn't hard at all.
Hornbreaker Prince is the Champion in this run. Though he has one frontline build, his initial health, while the best of the three upgrade paths, is not impressive and he can fail scale quickly enough defensively, so it's risky. I like his backline builds better, especially Multistrike. The problem with Multistrike path is its lack of initial damage and lack of ability to scale that damage on its own. But Multistrike build have amazing damage potential with the right support. In this case cards that give Rage such as "Ritual of Battle", "Fledgling Imp", "Rage Serum" and effects that amplify Rage are what you are looking for.

Again, the main task is taking advantage of the status effects better than enemy units, but with different pair of clans now (Pyreborne main and Banished secondary). The only other nuisance in this run is that you have to choose your cards more carefully since you forced to get another copy when you pick a card, but that's a minor thing.
Gold is doubled by "Moneybags" mod, but also Avarice status effect is doubled by "Duality" mod and gold gained from Avarice is quadrupled as a result! This means that probably you won't even be able to spend all gold in the end.
Lord Phoenix is a champion unique in that he has ability "Fenix Fire" on all his paths. It deals damage to a targeted unit and applies pyregel with an additional effect which is determined by upgrade path. Lord Fenix's paths all value being able to use his ability at key moments in the fight, and generally as often as possible. Relics, cards, and equipment that help him use it more often, like "Pyreborne Brainspike", "Taskmaster's Lash", "Mind Cage" and "Tome of Contracts", are very valuable.
Thanks to his ability to apply pyregel Lord Phoenix quite effective unit against bosses. Although he is usually mediocre against waves of opposing creatures and he is not a very combat efficient unit overall.

Umbra clan is the most distinctive, the most different in terms of playstyle. Additionally Umbra here is paired with Melting Remnants, which are not trivial in terms of play as well. This is perhaps the only reason for possible difficulties as only one mutator is negative and it's not a big one.
Penumbra is a champion that usually requires a lot of attention, either in the need for Morsels, floor capacity or survivability.
"Monstrous" path of Penumbra providing some of the highest raw damage and health of any unit in the game, which is great in early fights and I like it a lot. However, even with these big numbers, this champ won't be able to win the game on his own, and by the endgame he'll rarely be able to kill even a single 500 HP tank without significant support. This means that all of his paths benefit significantly from Trample and Multistrike. Fortunately, the clan's native spells can give those status effects ("Umbra Stone" and "Furnace Tap"). If you can't give Penumbra the support he needs, it's best to place him on a random floor you won't be using and focus on other units, though it's waste of his big stats and I don't recommend this.
The third level of "Monstrous" is unplayable without a source of additional space, because it require 6 capacity.
The Monstrous Penumbra is very good at wave clearing, but with some survivability support he can also become a boss killer. Lifesteal is very relevant to keep Penumbra alive and take advantage of his high base stats. Pay attention for sources of Lifesteal during a run to support him.

This one is completely trivial. "One Track Mind" is only negative mod and it's minor.
"Race Ya There" mutator is mixed of positive and negative, to which you need to adapt. This mod demonstrates the powerful effect of floor stacking beyond capacity. Capacity is not much of a concern this time, though capacity limit for a floor is 7 units and that's very important to notice with "Gravity" and "Race Ya There" mutators. Also notice how Shift works with ascending/descending. Any "Shift" unit you place on the first floor will likely be heavily activated due to its auto-ascension, as well as the auto-ascension of other units. You can't do multi-floor strategy this time, but this is not such a big problem due to strong champion and general mushroom strategy of floor stacking.
Going full "Rally" with Bolete as your champion is plain and powerful, because starter card "Eager Conscript" already available for scaling and it's the foundation of the build and it's relevant till the end. At the same time Underlegion is on of the best clans to get a win with. When you're struggling to pilot one of the weaker/complicated clans, then Underlegion as partner clan often helps, besides switching to them is simple. "Decay" debuff is pretty simple to apply. Common combo of Spore Launcher (apply decay on unit spawn) and Cluster Colonel (spawn units on resolve) can get you far. "Rally" is an alternative win condition that's straightforward and incredibly easy to switch to, if you're not finding decay units. Moreover it's fine to combine both decay and rally effects, and you should do it if possible.

I guess it wasn't supposed to be that easy. Considering the description of challenge, this one isn't well balanced and rather failed conceptually. Too small a penalty does not balance out the large advantage, making this trial almost trivial. Also only units penalised, but spells and other cards not...
Thanks to "Upgraded Drafts" mod, you save a lot of gold on free upgrades that you should spend on deck thinning and other improvemets. And "All cards have 1 additional upgrade slot" is simply huge.
Lady Gilda is a unit that mostly focuses on economic value. Main problem is her large size as she require 3 capacity units minimum, though this can be mitigated with effects like "Heaven's Light" relic, Smidgestone and natural 1-size units.
Her Harvest path (Bloat Matron) is most complicated and situational. You're relying on whelps the number of which is limited and there is no synergy with Luna units. Don't recommend, but other paths are more universal.
Avarice path is relatively straightforward. This build benefits from units that can trigger Avarice multiple times, like Bloated Whelps (their Indigestion ability damages all enemy units and earns gold for every unblocked hit), or units with Sweep or Multistrike or Trample. You may also try to stall relentless fights to get more gold. This path struggles in early game due to capacity limit as Lady doesn't have Avarice herself.
Egg path (Gildmother) has some of the best starting stats and Trample, but the whole floor will be occupied. She needs to be placed on the top floor to protect her Gilded Egg. You'll earn a lot of gold and relics from her egg celebrate, and this can be supplemented with additional hoard cards, but you should only need a couple.

Covenant rank 5, but in terms of negative modifiers this mission is not difficult.
In this run you will get two Champions. One is always Talos of Banished clan and another one is random (but not completely) champ, which can't be from Hellhorned or Banished clans. There is also unconfirmed info that the alternate champion from "Team Up" mod is always a MT1 clan. The issue here is that random champ likely has no strong synergies with Hellhorned or Banished. Component of luck has a strong influence here, because you can get a competent self-sufficient fighter or a unit which will be almost useless in fight. But even with unlucky RNG roll it's very possible to win a run with such burden in your deck.
"Brawl" mod makes squishy backliners more tankier, but this is only troublesome at the beginning of the run.
Talos is a Buffer type character focused on supporting the team. Depending on the path, she can either buff damage of units through status effects or provide permanent scaling over the course of the run. Her "Flight" ability has non-obvious benefit for shift-oriented troops of the Banished, because it triggers Shift on all units on both the starting and the object floors. Also it allows you to bypass the floor capacity limitation.
I don't like her starter card "Inspire" as it's kind of weak without stacked floor, also it's less useful and straightforward than Fel's "Just Cause".
"Enchantress" is a risky champion path of Talos that can grant a significant amount of stats to all your units if they manage to survive combat. This path is interesting to take if a strong fighter drops out randomly at the beginning. Otherwise, if you have weak starting cards, then the build based on Celebration will be a bad decision.
"Battle Cleric" aka Valor on resolve is the safest pick for a weak start, as 2 Valor per turn to the entire floor is a large boost for Rings 1-3. And "Celestial Radiance" aka Melee Weakness build have a weaker first fight, but outside of it this path is usually the strongest. On this path the trigger ability grants a massive indirect boost to damage output when she moves using her flight, allowing other units to deal much more damage. Picking up and using additional Shift cards should make clearing waves easier.

One of the first challenges where you require to adapt to specific modifier setup and there is little room left for alternative strategies.
The main problem is that it is impossible to implement a multi-level strategy. Also deployment phase is complicated by "+1 size downside for all friendly units". Another problem in this kind of challenge is to clear initial two-three waves due to friendly units entering with 7 Sap debuff and until the moment your first floor get well stacked. Units with passive damage like Prickly Puffball or some tank-unit with "Shield of Wyngh" equipment are very helpful tools in this circumstances.
Pyre of Savagery can be pretty strong in some builds, in context of this mission it's rather good with carry type of Fel, I mean "Unchained" path for her. Though you will suffer in first couple of battles, because this advantage accelerates extremely slowly. The other drawback of this pyre is that it's quite fragile, so taking risk with Invasion trials could be a bad idea.
The size-reduction upgrades here are unexpectedly good due to "+1 size downside for all friendly units" negative mod.
Remember that capacity limit for a floor is 7 units, you have to be careful here with "Gravity" and "Race Ya There" mutators. Also want to admit that "Gravity" mod is profitable for Fel's path with permanent Valor, because when any unit changing a floor with her it's counting as shift for both.

Again, in my opinion Umbra clan is the most distinctive, the most different in terms of playstyle. Penumbra is the Champion again, you should already know how to deal with him.
Cultist dudes seems very hindering, but with time you should adapt and take more and more advantage of them, as you'll take synergistic cards and capasity improvements throughout the run. There are two general solutions to "follower issue" - to sacrifice or to buff them. Both methods could be combined, though.
"Reanimation Lab" room is especially useful to buff tiny units as morsels and cult followers. Also "Glass Cannon" equipment can be used efficiently with followers, for example. As for sacrificial theme - both Umbra and Lazarus have many tools for this implementation.
The size-reduction upgrades here are unexpectedly good due to "Gluttonous" mod. Though stacking many banner-units on one floor is not necessary as this is against playstyle of Umbra clan.

Fortunately, it's only Covenant rank 1 and there is no Scourge cards in the deck from start...
Room combat previews are turned off, which may seem scary, but that's actually not the reason to worry much as enemy actions do not vary, because they're fully determined as well as waves for a certain fight. Preview just shows the net effect of an action, so "The Math Challenge" mod is rather annoying loss in quality of life. Disabled preview won't be able to do much harm if you know how to build your defense correctly.
"Magic Hands" mod is weird, because holding your hand is advantage and -2 cards drawing per turn is HUGE disadvantage, but I want to note that this drawback can be rather fixed during a run. The main challenge is how to get the cards you want with such limited draw each turn. This can be obviously fixed by "Limbo's Solace", which is important here. However you may build the deck to be weighty, I mean all cards with low impact that also often have cheap cost are detrimental, as you have limited draw and have to draw past them first. In this context it's better to remove "Witchweave" starter cards as fast as possible, IMO. Also in this case Intrinsic and Holdover are especially helpful spell upgrades to have. Units, spells and relics that increase card draw are highly relevant to overcome restricted draw stat in this challenge.
As for "Frontloaded" mod - taking into account "Aquath's Reservation" pyre, you will have not 20 energy but 23 at the beginning. And 23 energy is alot for early fights, as they're consist from 3 waves, so in fact this is an advantage in first half of a run. But the further you go, the more energy will be lacking, as there is already 7 waves in last combat and don't forget about deployment phase, so only there "Ember is limited". There is plain solution like "Hell's Flame" relic which will allow actually gain 1 energy per turn, and there is more unusual solutions to energy issue as well, including "Boiler Room", which is amazing in this challenge.
Also, in this conditions it is difficult to rely on spells if you have not managed to find a decent energy solution during this run. And X-cost spells under ban this time. Finally picking up a lot of Deployable cards and units will help, since you will have plenty of energy to set them up, and starting with a strong troops makes the cards you draw less important.
Champion Paths of Dr.Orechi vary wildly in effect, from turning into a living bomb to brewing infusions to help his team. Each of Orechi's paths require a different method of investment, and as such it's generally best to go all in on one strategy. "Brewmaster" is the simplest path, as your only worry is which infusions to generate with his ability. "Reanimator" is his most weird and non-obvious path, turning him into a living bomb so long as you can apply enough Unstable and Reanimate statuses. "Mad Scientist" is his most straightfoward path, giving him an easier offensive choice if you focus on spells.

This one is my favorite, because this is super FUN mission. This is the climax of ideology behind "Adapt to Distinct playstyle" type of missions. All three mutators are about random effects and your champ is a mad doctor Orechi, which is the best in terms of fun playstyle. Fortunately, this is Covenant Zero run and that is rather good as five extra cards from start could ruin the deck if the RNG results are bad, and that's a pretty big chance here. Well, sometimes starting RNG can be lame and make the run harder or easier, which makes it more about luck than strategy.
"Volatile Gauge" can be strong under some conditions and it require adjusting the deck. Volatile Gauge sets the cost of each card in your deck to 1.5 energy on average and draw +2 cards each turn. Extra 2 cards per turn provides value on its own, cards costing 2 or more have better value than they normally do, and cards costing 1 or less have worse value than usual. The higher the card's cost the higher its benefit from Volatile Gauge's randomized cost. X-cost cards are unaffected by Volatile Gauge, which can make them a bit more valuable as it provides a place to spend energy that would be otherwise wasted. Extremely expensive cards (4+) will always have their costs reduced by this relic, making the effect strictly beneficial. Cards drawn with Volatile Gauge respect any Ember reduction effects applied from upgrades or other artifacts. That is to say costs are randomized before upgrade modifications are calculated, so a card with Emberstone will cost 0 50% of the time, and 1 and 2 each 25% of the time.
Also in this challenge spells hit random targets and units shuffle the spots randomly every turn. Spells can target any unit on the floor they could rightfully target, including both friendly and enemy units. This circumstance makes this challenge extra tricky, because the spells do not work the way they normally do.
Offensive spell like "Dragon's Breath" is very good for this challenge as it can only target enemies and it's expensive that is kind of a plus here. Also, the equipment is more useful than normal because it is like a spell that is not affected by the negative modifier. Finally frail units with low health are not very suitable here, as it will be impossible to protect them consistently.

"Spell cost +1" is a strong negative mod, which makes focusing on spells extremely difficult. But there is also a penalty that affects your units, although not much. It's "Lose 1 gold whenever a friendly unit takes damage" regardless of whether your unit get hit to armor or not. But there are a lot of capacity for compensation.
There is little point in placing stewards on the floor, since the fewer units there are, the less gold is lost. So it's better to get rid of them as soon as possible.
Sap debuff is extra relevant in this run as you don't get the penalty if enemies don't attack.
"Inferno Room" is usually great, but here it's even greater. Because the less enemies hit your troops, the less gold you lose. Obviously, Inferno Room should be made deployable as fast as possible.

Your units are penalised with Dazed 2, but spells are heavily strengthened. So it's beneficial to focus on spells in this challenge. I would say that a successful start in this challenge is quite dependent on luck because of the champion Ekka of Luna clan. If you don't roll decent fighter or combat spells, you might not survive the first couple of fights...
Ekka has the potential to be an excellent support unit for any build, but her weak health makes her difficult to keep alive without a sturdy tank in the early game. Well, she can't do almost anything in first combat if some weak unit randomly rolled. She is best paired with a secondary clan that has access to spells that also scale significantly from Conduit.
Moon cycling aka "Lunar Steward" is her most problematic build. She doesn't have built-in phase manipulation, while natural Mooncycle is far too slow to rely on. Also you're relying on a few units (I have to say that these units themselves quite sucky) that offering additional Mooncycle triggers, which is unreliable.
Conduit stacking aka "Celestial Spellweaver" is her most consistent and simple path. It benefits from her 0-cost "Witchweave" starter card. Entire strategy revolves around spamming spells on her floor, leading to massive Conduit stacks and making even her small Witchweave hit or heal incredibly hard in later rounds. But her health will never exceed 8 HP.
Full Moon build aka Silver Empress is a difficult path due to a lack of moon phase control. But rank 3 of "Silver Empress" provide 70(!) Conduit at full moon, which is equivalent to more than 20 Incant triggers for Conduit stacking. I think the result is worth all the hassle of assembling this combination together. While it's still unreliable, at least the worst case scenario is that you'll be blowing up everything around every other turn.

This time there is no Champion, but this is only problematic at first.
Train Stewards are not powered-up from start, but they have potential to grow thanks to "At Your Service" mod. Under existing conditions, you may fully focus on Steward units, but this isn't necessary. Moreover it would be more reasonable to combine them with other types of troops. But anyway, it makes sense to keep and improve your Stewards. Installing 3 upgrades on a steward gives him +30 attack and health additionally, which is a lot. Be sure to force 3 upgrades on one Steward first so you have a chance to add a fourth upgrade through the Cavern event. Starting with Shield Stewards is better, since they are deployable. And "Steward's Quarters" is obviously the room you are looking for.

This challenge will not seem particularly difficult, because both clans Banished and Lazarus are strong, but in my opinion this would not be the case with other clans. Though Lazarus is one of non-obvious and more complicated clans in terms of playstyle.
All units get Multistrike 1 including bosses, which is quite scary. Because of this, your frontliners will be subjected to serious pressure. Luckily "Strike Hard" modifier works on your units too, so it's not all bad. Though enemy units enter with Spikes 1, which makes your backline fighters vulnerable too. Test Subject Alpha (sweeper of Lazarus) is especially vulnerable under this conditions and under ban in this run. Taking units with low HP is unwise until you solve the problem of their survivability. Also enemy units gain Spikes 3 when they move. Fortunately this modifier doesn't work on flying bosses until the final wave. By the way, this is the reason to put the main defense on the first floor, because you don't want enemy troops to get stronger as they ascending.
Inferno Room is usually great, but here it's amazing as it's a great solution to backline enemies. This allows you to reduce the number of dangerous enemies that will reach the main combat floor. Obviously, it should be made deployable as fast as possible.
Valor is a Buff that is heavily used by the Banished clan and it's very helpful for your frontline units in this mission. Firebrand (Banished unit) can confidently carry a run on this challenge, as its "Revenge" trigger ability will be constantly activated by enemy attacks and spikes. Another great Banished unit is bird with Saxophone (Upbeat Warbler), which gives all friendly units on his floor Quick buff. This unit is especially strong on floors that have good damage capability or with Sweep units, as he saves upgrade slots for units that would need Quick and allows you to clear floors of normal enemies without taking damage to your units.
Pincushion is a unit of Lazarus with permanent scaling on eqipped equipment that can be found very early in the run. Pincushion is a very slow scaling card under normal conditions, but combo with Baron Grael's Erratic Assistants makes him quite stong tank and damage dealer at the same time.
Baron Grael champion is Buffer-type unit that focuses on equipment theme. It is not recommended to remove his Erratic Assistant starter cards, as they provide a constant source of cheap equipment, scaling and buffs.

It's only Covenant 1, but, damn, this one is tough! In no small part because Lord Fenix champion suck ASS, at least at the current moment. Well, I'm being overdramatic, but he's only tolerable in my eyes as more like an economic/meta-scaling unit since he won't help much in combat. Don't get me wrong - he is useful in combat, but your first raw should consist from more combat-efficient fighters. So I prefer his "Golden Crown" path, when he's sitting on second/third floor, farm eggs and occasionally fighting. There is minor issue however - sometimes there are no target to use his ability more often, but I'll tell you a little trick. He can spit fire at your stewards on the same floor and other friendly units as well.
What about Devilish Collectors? They can be rather dangerous early, but they provide a lot of extra gold that should be used for improvements. "Skull Collectors" mod is not straight negative as it's an upside if your build is strong. Otherwise, these are tanks that sitting on the floor and covering enemy waves.
The main problem here is the "Shields Up" mod, which requires you to hit each enemy once before actually being able to damage them.
There is other solutions to "Enemies enter with Damage Shields" issue, but most common solution is "Flicker". "Flicker" spell is a card that is generally of no interest, as it is more of a blank card than a full spell. However, in these circumstances it's almost mandatory to remove shields from enemies. Also it needs be upgraded with "Holdover" to become a full-fledged problem solver.

"U Can't Touch This" challenge type. This time you need to be especially careful with fragile pyre, and avoid getting greedy on trials.
Run's difficulty is set on Covenant rank 6. This means this time you have two "Vengeful Shard" in the deck, which are very disturbing.
Beware the many ways you can take Pyre damage, as even 1 damage will cost you a precious Damage Shield stack. The Vengeful Shards, creatures that add Scourges and effects that hit your Pyre if there are no units on the floor such as Arkion's Pyre Hunter variant and Terrifying Amalgams are major threats here, since you won't be able to place your units on the bottom or middle floor to counter them. To combat this problem, look for cards with effects that apply Dazed and Mute.
Largestone is a relevant unit-upgrade in case with auto-ascension as capacity limitation is not as restrictive as usual. But remember that capacity limit for a floor is 7 units as that's important with "Gravity" and "Race Ya There" mutators.
"Unnamed Tome" is very relevant spell of Stygian clan in this mission as it's neutralise various Scourge adders that are extra dangerous in this mission. Additionally it's one of the most universally useful cards in the game, as Mute status counters great number of dangerous enemies triggers and abilities.

This challenge can't be solved with many different strategies as you are pretty much forced to rely on spells in this run. In no small part because "Ninja Training" mod is one the worst that indirectly weakening your troops.
Drawing cards from the deck will be super difficult due to "All spells gain Holdover", that's why you'll need small to some extent deck and you have to be super careful when adding cards in this challenge run, because the draw order can put your key spells on the bottom of the draw pile. Also when more than 4 spells played (without additional card draw source) in a turn, you don't cycle the deck in the next turn! So you should not play any spells which you do not want to draw again on the next turn.
In the context of this challenge, your goal is to draw as fast as possible small set of most efficient spells and play them all every turn as they will always be drawn again on the next turn. "Seekstone" aka Intrinsic improvement is especially necessary as you want your key cards to be drawn instantly. Card removals is very important here too.
There is interesting trick that can be used in this trial. Considering all spells have built-in Holdover, you can play and return up to 10 (hand limit) spell cards on your next turn no matter how much cards can be actually "drawn", obviously if you have energy to play all hand. So if you have source of card-retain or one time use draw-effects, then it can be used to advantage with smart play.
Considering enemy Shields, "Witchweave" is very useful card (especially when upgraded) and "Frozen Lance" is annoying crap, which you want to remove ASAP. Another option is putting Consume on "Frozen Lance" to prevent them from going back on top of your deck and blocking drawing other cards.
Also don't forget that Pyre have ability to generate 3 energy once in the battle, which, unfortunately, not that useful in this run.
Tethys champion is a Glass cannon-type character with the ability to put out large amounts of damage, power up damage spells and even reduce their energy cost, but low health. It is important to put effort into keeping her alive regardless of upgrade path, especially in last fight with Seraph. This makes cards which can apply effects like Armor, Damage Shield or raw health very useful to mitigate her very low base HP. Regardless of upgrade path, Tethys should almost always be placed in the backline. Being only 1-space unit helps with this though.

It's true Roguelike challenge with Permadeath! "Permadeath" mod is not entirely bad as you could and should benefit from removing weak/irrelevant units (Stewards). In these circumstances, you should be more concerned with survivability than damage. Your tanks should become indestructible, but this rather depends on luck in getting the right units and upgrades. Don't recommend to take risks with trials in mid game, until your team is completely OP and you are confident that they won't die.
"Yeetpocalypse" aka mandatory card purge is very bad. It doesn't seem that way at first, though, because free card removal is so cool! Because of this, you need to take any cards that are offered during the drafts, no matter you need them or not. And you have to be super careful when deciding which card to keep and which to sacrifice. By the end you may just buy whatever cards at the "Merchant of Arms" for the purpose of simply sacrifice them.
"Vampiric Touch" is rather positive mod as Lifesteal 3, unlike enemy units, is big for your units, because they can deal hundreds of damage and heal for the amount of damage dealt.
Arduhn of the Luna Coven is a Champion. He is a hybrid of a tank and damage dealer with a magical bent. His attack damage is enhanced with Mageblade and scales with Conduit (counts all Conduit on the floor not only on the unit who has it). His innate Mageblade scaling can be increased with "Battleborne" path, but this is inappropriate path for this challenge. Much more preferable are the paths where he can be a tank.
"Mystic Hammer" is Arduhn's most straightforward path and by far the most powerful path in early game. His high base damage and HP make him a useful unit in any run.
"Hierophant" build is more suitable for those who focus on magic. Here the champion has more emphasis on defense than damage, and this is the defense of the entire floor. This build is probably the best fit for this challenge.

It's not called Agony for nothing. All modificators are negative, alas. Covenant rank 5, but what's worse your Champion enters with sap 10 and Heartless, friendly units get Heartless as well and can't be healed in any way. Additionally your deck burdened with 5 deadweights.
Well, at least you have Pyre of Entropy, which is special. It's tanky and draws 1 extra card for every 2 Blights in your deck, so draw stat is great. You'll start from drawing 7 cards per turn and to the middle of a run you'll be drawing full hand every turn, though half of hand can be literally deadweights. The downside of this Pyre is that your deck will gradually fill up with "dead" cards. To counter this it's reasonable to draw more cards than usual when drafting. Having more units and spells, even mediocre ones, will help you draw useful cards more often than deadweights. "Sinner's Salve" is excellent relic with Pyre of Entropy.
Thankfully, Madame Lionsmane is not affected much by Sap. Avoid cards and upgrades which provide healing or regen, since these are useless with "Heartless" mod. Although it is unlikely, but it's possible to take advantage of Blights. "Looming Darkshard" (relic which can only be obtained in the Archus event) will grant 1 energy and draw a non-Blight card when Deadweight is drawn. Other Blight synergie is "Dante the Dependable" (obtainable only from a Celestial Alcove event). Dante, already a powerful unit, is run-winning when using the Pyre of Entropy.
Madame Lionsmane is a champion and her most appropriate path for this challenge is "Sporesinger". It requires no additional input to work effectively, automatically applying increasing amounts of Decay to all enemies on the floor every turn. However, it is at its most powerful when you can use other units or spells to apply the Decay effect. The Spore Launcher is especially powerful, as it frequently applies small amounts of Decay to all enemies, with each activation gaining the extra Decay from this path. Also this is the only path which benefits significantly from her starter card "Sporetouch". "Sporesinger" is just passive damage build, this is what you need and without any unnecessary fuss.

It's second true Roguelike challenge with Permadeath! "Permadeath" mod is not entirely bad as you could and should benefit from removing weak/irrelevant units (Stewards). Another penalty is "Spell cost +1", which is nasty.
Rooms are important and only advantage in this run as they're all zero-costing. In this context, room/equipment shop become very interesting.
Luna coven is kind of spell-oriented clan and your starting deck consist mostly from spells, but spells are heavily penalised this time. Alas, relying on spells is not an option due to "Spells cost +1". But units penalised too. Most of Luna's units aren't very strong on their own, and they're burdened with Permadeath. Fortunately, Arduhn champion have tanky path to cover vulnerable units and he is competent fighter. Unfortunately though, as it's Covenant 1 run, it's quite possible in the beginning randomly roll a few weak units, 4-costing spells (which are dead draws) and rooms, which don't provide an immediate advantage either.

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