This guide assumes you have unlocked all relevant meta progression upgrades:

• All Boneraise Lore meta upgrades to max level.
  
• All Heroic Force meta upgrades to max level.
  
• All Class Heritage meta upgrades for the class you're playing.
  
• All of Goblusious's unlocks under "research powerful relics".

It also assumes you have enough Gold Coins and Hero Souls to buy relics at the start of your run from the merchants, and to build contraptions in your chosen map as described in the Setup section. It's possible you can still achieve an infinite without all of these things, but they will definitely make your life easier!

I originally wrote this guide playing on v31.6 of Boneraiser Minions. I wouldn't be shocked if these strategies get patched out eventually (or quickly!), so please be aware and check the relic, spell, and contraption behaviors on your version before attempting it for yourself!

March 24, 2023 edit: Two changes have been patched in which hamper infinite strategies:

• In v31.8, Regrowth Returnal was tweaked to benefit contraptions more the fewer of them you have. I'll need to do some testing, but this likely means you won't get full restoration of your Treasured Chesty contraptions from a fully-charged Level 1 cast anymore.
  
• In v31.10, the maximum level of the Enbanishment Scroll relic was reduced from 9 to 3. Even though all 9 weren't needed to spark the infinite, 3 is certainly too few and will have to supplemented by Enbanishments from Traveler events and the Blank Scroll spell if you hope to get the infinite working.

Seeing these changes, my suspicion is that the infinite is still possible with very good luck, but much much harder to achieve. You might have to grind out dozens of attempts to get sufficient Blank Scroll luck to earn enough banishments, for instance.

As of time of original writing, I had the top score as Imp Contraptineer on the starter map's leaderboards (by a healthy margin!) using an the strategy described below.

As the Imp Contraptineer, we'll be able to survive infinitely once we have:

6 Treasured Chesty contraptions: We'll need to play as the Imp Contraptineer class to make this possible.






A bunch of Banishments: Via the Enbanishment Scroll and Horoscope Charm relics, Traveler events, and Blank Scroll spell, we need to banish enough spells so that...





Regrowth Returnal is one of only a few unbanished spells, so that we're offered it every time we pick up a spell scroll. That's because with...






Sorcery Wand: Even at Level 1 of this relic, a charged cast of Regrowth Returnal will completely replenish a freshly-opened Treasure Chesty contraption; at Level 3, an uncharged cast can do the same. This lets us regrow and open a bunch of treasure chests, so that...




Magnifying Glass at Level 3: With this relic, we'll have a 2/3 probability of finding either a relic or spell in each treasure chest we open. For our purposes, what matters is the 1/3 probability of finding a spell. Every time we replenish all 6 Treasured Chesty contraptions, on average we'll obtain 2 Regrowth Returnal spell scrolls, which allows us to repeat this again and again and again. Finally, with...



Bernard's Watch: With this relic, we get 2 seconds of invincibility each time we pick a spell (or relic) from a treasure chest. 2 seconds is more than enough, but just to be safe we can upgrade it to Level 3 for a full 4 seconds of invincibility, more than enough even if we slip up in our movement.




With the above, we can do a lap around our Treasured Chesty contraptions, get at least one cast of Regrowth Returnal out of them, use it to regenerate all 6 chests, and remain invincible thanks to Bernard's Watch, and pick up a ton of gems and relics for a truly absurd score.

Technically, this is not a perfect infinite: it's possible to be offered no spell scrolls across multiple laps of treasure chests and eventually run out of Regrowth Returnal casts. However, once you have a full inventory of spell scrolls, the probability of this happening is about 0.0059% -- and with the Magical Bum Bag relic, which we're bound to obtain eventually from a treasure chest, the probability of whiffing from a full inventory of 5 spell scrolls falls all the way down to about 0.000046%! We can expect to complete over two million laps around our treasure chest farm before whiffing even once.

Before starting our run, we'll make the following preparations:

1. Lay out Contraptions: In Architect Mode, fill the chosen map with as many of the most expensive contraptions possible, from the bottom two rows of the menu. The Imp Contraptineer can sell these for Scrap once the run begins, so by filling the map with expensive ones we'll have lots of Scrap right away to start building Treasured Chesty contraptions.
2. Attune Giga Banishments: Use your Giga Banishments to remove up to nine spells and relics from the pool of choices, boosting the odds of finding the ones we want. Remove whichever you like the least!
3. Pick the Imp Contraptineer class: This will let us get a maximum of 6 Treasured Chesty contraptions once the run begins.

Make your preparations, then begin the run! We're offered two upgrades from the Blacksmith at the cost of Gold Coins, then one upgrade from the soul eater friendo at the cost of a Hero Soul. We can quickly reset the run (via the pause menu -> Quit -> Quick Restart) until we find what we want, namely:

1. Blacksmith relics: Look for two of the following: Watering Can, Enbanishment Scroll, Crooked Dice, Horoscope Charm, Sorcery Wand; as well as anything you find helpful to survive the start of a run. We'll prefer relics that help set up the infinite (Enbanishment Scroll, Crooked Dice, Horoscope Charm) over ones that are helpful once it gets going (Skelly Key, Spring Sandals). Unfortunately, it does not seem to be possible to get Magnifying Glass here (I've never seen it be offered).

2. Soul Eater boon: Buy the Enbanishment Scroll if it's offered, or re-roll for it. It's offered often enough that you should be able to get it this way in the vast majority of your attempts.

If we got what we wanted, the run is now underway!

At the very start of the run:

1. Cast your starting spell to get rid of it.
2. Run a lap around the map, using your unique Imp Contraptineer spell to sell all of your contraptions aside from the two starting Treasured Chesty ones. While you're doing this, open the two starting treasure chests when you encounter them.
3. Buy as many Treasured Chesty contraptions as you can, placing them next to your two starting ones. You should have enough Scrap from selling to have 5 of them (out of 6 maximum) right away.

To make your life easier in the early game, you may want to spend some of the excess scrap on other contraptions to help you survive: I really like the Honeycomb Beehive, Bushy Fruit, and Blood Barrel contraptions for max health and Occult Hearts. This will slow you down towards your sixth Treasured Chesty, but in practice having all six is not especially important until the combo is well underway.

You can freely boneraise your favorite minions throughout the run, but it's good to prioritize the Trapper Impling and Daemonic Impling because your Class Heritage bonuses will grant you more Scrap per second for each of them that you have, speeding you towards the final Treasured Chesty!

As far as I can tell, all Banishments are shared across relics and spells, so be sure to save them for spells by not using any on relics. However, you can freely re-roll relics to find the ones you're looking for, which in the early game will be any that make it easier to assemble the combo and survive.

The timing of your first relic may vary depending on your chosen map, but generally you'll get the first relic from the first wave of armed peasants, a little over a minute into the run. I recommend resetting the run if you're not offered the Magnifying Glass, because it's absolutely essential, as described below.

These are all the relics you should keep an eye out for, in (roughly) order of importance:

Magnifying Glass: Not only is this essential to the infinite, it will net you even more relics and spell scrolls if you obtain it before your first 5 Treasured Chesty contraptions respawn. It's also the only required relic for this strategy that you can never be offered at the start of the run by the Blacksmith, and it's one of the relics you can have the Blacksmith upgrade to Level 3 later on. The earlier you get it, the better.


Enbanishment Scroll: You'll need as many of these as possible, so prioritize them above all other relics aside from the Magnifying Glass at all stages of the run.





Crooked Dice: Grants six re-rolls -- that means seeing another 18 relics! This will maximize your odds of finding all of the necessary relics.






Horoscope Charm: Grants a re-roll, enbanishment, or sealment when you choose the bottom-most option of those offered. Re-rolling helps to find the right relics and the right spell when it's time to get the infinite started, and enbanishments are crucial to ensuring you're offered Regrowth Returnal with every spell scroll. Even if you forget you have the relic, you'll still get a bonus on average once for every three times you select something! Furthermore, since your choice of boneraises isn't all too important to the strategy, you can pick the bottom option often to maximize the benefit of this item.


Watering Can: Though it'll be useless once the infinite starts, this relic will make the Treasured Chesty contraptions regrow faster and (once you have the Magnifying Glass) get you more relics and spells across the course of the run. It can also gain you more Max Health and full heals via the Bushy Fruit contraption, if you're using it. Remember as well that your Class Heritage meta upgrades are already making your contraptions respawn faster; with this relic, that bonus gets supercharged to even more amazing levels!



Service Bell: Can summon a merchant to sell you relics or spells, increasing your odds of getting the ones you want.






Crystal Ball: There's a Traveler event that can grant you a relic and another that can grant you more re-rolls.







Sorcery Wand: An essential component of the infinite that's also useful early on to get the most out of your spells. This strategy benefits a lot (by design!) from casting Regrowth Returnal, especially once you've picked up the Magnifying Glass, so having this relic will help you get more relics and spells.




Aside from these, grab any relics that will help you survive and any others that contribute to the infinite (listed under "The Plan" above).

When you find your first spell scroll, you can spend three of your banishments to remove three unwanted spells from the pool forever. In most cases you'll want to banish as many as possible, but there are a few useful spells I recommend keeping around until the infinite is nearly assembled:

Stars Alignment: You can get as many as six (!!) re-rolls from a single cast of this spell, making it potentially as good as the Crooked Dice relic.






Travelers Lure: You can get additional re-rolls from a particular Traveler event, and a relic from another.






Magical Chest: When charged, this spell has a chance of making two treasure chests appear. Thanks to Magnifying Glass, you're likely to get another spell or a relic from each cast of this spell.





Blank Scroll: This can grant an all-important banishment, speeding you along in reducing the spell pool.







Once you have enough scrap (6750) for the final Treasured Chesty contraption, place it down near the others. The closer, the better: you want to be able to complete a lap collecting all treasure chests as quickly as possible.

Along with the relics mentioned in the prior section, and the relics mentioned under "The Plan" as essential to the infinite, you should watch for these relics in the mid-game:

Skelly Key: This will make your life a million times easier once you get the infinite going, by opening treasure chests instantly.






Bonechemist Slab: Grants bones from gem pickups. Treasure chests drop gems and not bones, so with this relic you can get infinite bones as well as gems and invincibility.





Ethereal Shoes and Spring Sandals: These let you run laps collecting your treasure chests more quickly, and allow you to outrun your chest pickups (as described below).




Magical Bum Bag: Allows you to hold more Regrowth Returnal spells at once, decreasing the chances of the infinite fizzling out, as described under "The Plan" above.

Even before you have all of the components described under "The Plan" above, you may get a Regrowth Returnal spell and get to run a lap or two around your treasure chests, claiming more relics and spells as rewards. Use these to help you gather the last couple of components that you need, and keep an eye out for how often you're offered Regrowth Returnal. Eventually, with enough banishments spent you'll see it every single time, which means you're very nearly ready to go infinite.

You don't need Bernard's Watch straight away as long as you're comfortably surviving, and once you get the infinite going you'll be deluged in more relics than you know what to do with, so you don't have to worry about having it straight away. Likewise, you can start with just a Level 1 Sorcery Wand, as long as you fully charge your casts.

You'll know the infinite is underway after you do a lap of your treasure chests and grab 1 or more Regrowth Returnal spell scrolls, then grab more on your next lap, and more, until you have a full inventory of them. At that point, congrats: you did it! You can keep running laps and keep selecting all of the relics and boneraises you desire until you win the run or get completely and utterly bored in New Game Forever. With the Bonechemist's Slab you'll easily be getting 1-2 relics/boneraises/spells per in-game second, ensuring endless invincibility thanks to Bernard's Watch.

I recommend running around opening all of the treasure chests without stopping (using the Skelly Key) so that your pickups don't reach you until your lap is completed. You won't be interrupted by the spell selection screen while you're charging a spell, so if you immediately start charging Regrowth Returnal at the end of the lap, your pickups will wait patiently for you and you'll get all the chests back and ready for another go before making your selections. This means that as long as you can complete a lap within 4 in-game seconds, you'll stay invincible forever.

• In theory, it's possible to execute this strategy as the Psycho Possessed class, since you only need the Imp Contraptioneer Class Heritage abilities to build all 6 Treasured Chesty contraptions, not to maintain them. In practice, this would be a complete pain to carry out, since you'd need to keep resetting runs until offered the class early enough. But hey: that means you could soar to the top of not one, but two leaderboards!

With the Imp Contraptineer version of the infinite effectively patched out as of March 24, 2023, I did some investigation and found a new version involving the Sorcerer Hollow

The Plan
It's very similar to the previous method, except it's not reliant on having extra Treasured Chesty contraptions.

Once we have:

• The Sorcery Wand at Level 3
  
• The Magnifying Glass at Level 3
  
• Bernard's Watch at Level 1 or higher
  
• Enough spells banished so we can consistently get Spellious Spewious and Magical Chest in (on average) one re-roll or less.

We'll be able to cast Spellious Spewious repeatedly, filling our inventory with more copies of it as well as Magical Chest. We can run around opening the chest and getting more spells to continue the cycle and earn an absurd score.

Unlike the other infinite, this one has a realistic chance of whiffing, which is mitigated by:

• Having a bunch of unopened chests lying around, which with Magnifying Class and Class Heritage abilities will tend to give more spells and relics.
  
• Earning an absurd number of re-rolls by casting Stars Alignment periodically. With a Level 3 Sorcery Wand, plus the Class Heritage ability granting increased spell power, we can get 9+ re-rolls per cast.

I've found that even if you do whiff and run out of chests, it doesn't take long to get more, especially if you boneraise a large number of Majick Doppelganger minions to help you out with random spells.

Why does this method work in spite of the nerf?

• The nerf to Regrowth Returnal is mostly irrelevant because you don't need to cast it once the infinite gets going. Each cast of Magical Chest should yield 2 or 3 chests.
  
• The nerf to Enbanishment Scroll is relevant, but mitigated by Blank Scroll. The number of banishments it grants scales with spell power, so we can easily get 3 or more per charged cast once we have a Level 3 Sorcery Wand. This is self-reinforcing, as each spent banishment increases the chances of getting Blank Scroll again and so on and so on.

This method may be worth trying with other classes, as I'm not certain the Class Heritage boost to spell power is strictly necessary to keep the infinite going... however, other classes are likely to be less consistent!