Since game is new and i am still learning, guide will be small and chaotic in the beggining. I will add some thoughts and observations over time. Refer to the last section (list of changes) to see what have been added.

Routes — are big types of strategies used to play. They are incredibly different from each other, have unique rules, goals and gameplay feeling. In the beggining player has access only to basic route with simple rules.

Basic route goal
Make enemy path as long as possible and force them to revisit same area many times. We have three switches and one exit, enemies will always move to switch 1 > then 2 > then 3 > then to exit. Since we do know how exactly they move around, it is easy to set a trap.

1) Make sure 'switch 3' is short distance away from 'switch 1'. If they are too far - consider restarting run;

2) Make a line from bottom part of "exit" towards 'switch 1';


3) Make a back door from 'switch 1' to switch '3' like in a picture;


4) Now, what we did there is very clever and sneaky. Enemies will move towards 'switch 1' using 'path 1'. Then they will reach dead end and have to turn around and move using "path 1" for the SECOND time to get out from maze we created. They will head to 'switch 2' using outer space we don't care about. Then they are forced to go 'path 1' for the THIRD time, cus guess what - that is the only way to reach 'switch 3' via small backdoor. Finally, after flipping last switch they have to move using 'path 1' for the FOURTH time towards the exit. You see what we did? Very evil.


5) Every time game gives you choises, pick '2 Towers' > then '1 Tower + xWires' > then 'xWires'. If you have just started playing or have less than 50 Salvage, it is good idea to pick Salvage before anything else, make it your priority. Salvage will be used later to unlock new Routes.

6) Now just increase size of 'path 1' as much as you can, since evey single tile inside of that area will be visited four times. I think there is no better place to increase overall path lenght. We can also call it "Kill Zone", cus that is where all enemies gonna perish.



Now since you know how to build basic mazes and make them very annoying for mob, we need to take care of another important part — doodads. From the first glance you might think every doodad will make you stronger, but it's actually the other way around. The more of them you pick, the weaker you become over time, since very slowly they will reduce your overall power and strenghten the mob. Take a look at this screenshot:


The first thing you should look at - if there are 2 good bonuses or just 1. Overall, having two good means much better chances to actually get a positive power change for yourself. Unfortunately, those are super rare. The next, you should always consider picking neutral ones to not harm yourself in long run. This is why i prefer picking Salvage, Towers or Wires — it won't cause any problems.

As for Epic Doodads, they switch gameplay into completly different route. Doing this in the middle of run, where you already established a base, kill zone, backdoor and towers, will absolutely sure destroy you in 1-10 upcoming waves. You simply won't have enough time to change strategy. Take that "Nova Core" doodad from picture as example, it reduces towers range (basic range is 6 tiles), so now their reach is only 1,62 tiles - they literally cannot hit anything that isn't right in front of tower. On top of it, enemy will 100% sure get +4 scientists EACH WAVE which will shut down towers in range of 5 meters over and over again.

The only reasons to pick epic ones — if you ready to end the round and want to permanently unlock that doodad for later use from wave 1 (which will cost 50 Salvage). You can have maximum 3 of epics active at the same time when starting the game and their combination is what i actually call a "route".

...


The first thing you can do to optimise any straight-line labyrinth is use every possible tile to make path longer. On screen shot below you can see basic tactic i used for a long time. There are many T-sections which look ok and from the first glance nothing can be done about enemies moving diagonally.



So the problem is - i have some extra wires and need to find a way to make path even longer. Just adding extra wires outside of tower attack range - useless. An idea poped up to use 2 extra wires to make a little gap inside T-section and force enemies go upwards 1 tile, then downwards 1 tile.



After observing whole maze i found quite a lot of such T-sections and changed them accordingly.



...


Unlike T-section, Zig-Zag tactic uses every possible square and cannot be optimised, but from other hand it will look the same every time you play, which is bad and leads to burnout (thats when you getting fed with game and uninstall it due to repetitiveness).



Since in Zig-Zag maze all towers are in the middle, make path to first Switch as long as possible and covering whole tower area (upper-left switch on screenshot). The best upgrades for this tactic are "+ Tower Range" bonuses, until their attack zone reaches borders of arena.

Effective tower is the one that shoots all the time without breaks.

This is grid i made from playing several long runs, ending at wave 70-90. I was carefully writing ammount of towers reached, so you can figure out how many is possible to have at any given moment. Also each time you choose towers doodad, your overall power increases, cus more towers will shoot. And i decided to show % strenght increase every time another +2 towers picked (sure sometimes you get only +1, but that's not important, just split the % in two).




Well, first of all, even picking +1 Tower at wave 80+ will give you dmg boost for 2,56%. So you can compare that number to other doodads and figure which one is better to pick. Maybe there is some rare one that can improve overall stats by 4-6%, then you should pick it instead of +1 tower. If there is +2 towers one, it's a +5,12% boost, i doubt you get better deal at that stage of playing, plus it always goes with extra wires.


Some players saying wires are useless, cus, apparently, they give 0% power increase. That is wrong! Imagine a big pile of crazy mob (15 of them) all having same stats and speed. They move ony one after another turning into some sort of snake. When snake reaches tower zone, it's whole body will be there getting hit. When it goes into outer space, towers have no targets to shoot. That is where you start losing!!! If towers are not shooting, you lose precious attack power, which could be spent on shooting something.

Now imagine a different situation, where enemy mob consists from 15 creatures: 5 fast dogs, 5 medium peasants and 5 slow brutes. They all move at different speed forming three 'snakes' - fast, normal and slow one. When 'fast snake' enters kill zone, it gets damaged, then leaves kill zone and goes into outer space area without towers... At the same time, medium snake just reached kill zone for the first time and starts getting dmged. They flip 'switch 1' and also quit kill zone... Now slow brutes entered kill zone for the first time and started getting dmged. They are so slow that you will be able to kill both dogs and peasants way before dealing with brutes. This way towers attacking NON-STOP and enemies getting damaged all the time.

Conclusion — by mixing enemies you able to create 3 different 'factions'. Now the question is, what does it have to do with wires, right? Everything!!! If you simply put 200 wires in straight line inside outer space, dogs will have enough time to separate themself from everyone else and gonna lead the charge. Brutes are slow enough to pile up in the tale this way. Without wiring long roads you will not be able to force them into splitting and istead, dogs will hide among brutes and peasants, while finally reaching exit and ruining your experiment.

Alright, that's where FrankenStorm really shines. In order to switch to this route you need epic doodad called "Fanaticism". It increases towers attack radius by 18 meters on top of basic 6, allowing to cover whole arena with towers range (just don't place them in corners). If you don't know, arena is 21 tiles tall and 35 tiles wide.

There are three drawbacks: enemy will regenerate +5% HP per second, can move over wires (like ghosts) AND another random debuff (i got enemy chance based effects occur +48% more often). This way we completly change playstyle, strategy and doodad effectiveness.


We need special type of arena that fits requirements:
1) 'Switch 1' generetad on left side of arena and not in a corners;
2) 'Switch 2' is on the right side of arena;
3) Distance between switches 1 and 2 as big as possible (20+ tiles).
A few examples of good generation:
After some observation i found that overall distance from entrance to switches / to exit can be super random, from 45 tiles to 100, so it will require several game restarts... Since we can't make it longer ourselfs by using wires.


The first thing you should care about is collecting double-basic doodads that increase Eagles chances to appear. We aim for 100% chance. Since enemies will ignore wires anyway, we no longer build mazes and trying to avoid wires picks. Birds move very slow and have low life, which will allow us to get extra time for tower shots. Also it's' just super fun to fight enemies which we would absolutely never pick in Basic Route, since it will cause lose very fast.

The next top-priority is attack speed, since sniper towers are focusing same low-hp target all at once. We gonna one-shot birds, so goal is improving attack speed to extent where we can kill them as fast as they spawn to prevent any movement.

Novas. Yes, if you gonna find another epic doodad called "Nova Core", sniper towers will turn into 'sniper machineguns'. This bonus reduces attack range by 72%, but all shots are dealing dmg to all enemies in range. You probably wonder, but what gonna happen if +18m range clashes with -72% range? Here is the video:
https://www.youtube.com/watch?v=olXJIdVPnp8

HP regeneration doodads is something we turned from bad to good. Since enemies already have 5% regen and we one-shot them, giving extra HP regen won't cause any problems. Most of the time doodads bonus is only 0,2%-0,3% so you can stack a lot of these to an extent.


The list is huge, but ltet's start from worst to less dangerous:

• +Movement speed — don't take it ever, you cannot counter it later;
  
• Giants, Dogs — no, even single one will make you lose at later waves;
  
• Stat bonus increase per wave (armor, speed, hp etc) — avoid;
  
• Healer and Scientists, have more HP compared to birds and will increase wave size;
  
• Tinkerers (will drop useless wires, adding +1 creature to wave);
  
• Dodge, speed up chance (not as devastating, but don't increase more than 20%);

Be careful with epic doodads, something like "Snow Day" can reduce enemy speed by 30%, but always consider negatives. Some of them (like +8% dodge) are fine to mix into this build, while others can destroy you immediately. Trial and error is the only way to find what will work. Going for +4 Medics or +4 Scientists is 100% lose.


After testing Sniper Route for several days i found interesting tactic... Reducing attack speed to -80% helps to stand longer. It works like that: you can pick negative speed doodads to trade for damage or other goodies, which allows to avoid some trully bad things. Then you just need to find ONE doodad that gives '+explosion range over time per second (up to 10 seconds)'. Now, if it gives even +0,2 range per second it means after reaching max time (10 seconds) of NOT shooting, your next shot gets free +2m attack range AoE. That is huge bonus and will kill several eagles at once. Stack 2 of such bonuses and you can kill 5-6 eagles instead of 1.

I calculated % speed and how many seconds you will need to wait to actually shoot once, here is the list:


The numbers are quite unusual and thats absolutely not how i thought it worked. After reaching -50% attack speed it starts to affect actual attack speed a lot and even slight change in % will have drastic consequences. Going below -80% is super dangerous, cus you will have enormous slowdown without extra benefits.

Using this tactic allowed me to reach waves 80-90 without problem every game. Also there are many different bonuses over time, like +damage and +crit chance. They all trully shine if towers are slowed a lot.

Some abilities are 'static', for example, if you give +2% dodge to enemies. If you pick another one (let's say +4%) it will add new static to old static, so final dodge is 2+4=6%. But there are also universal skills that change all enemy proc chances by some %. Those are "multiplicative" bonuses, which means they will multiply all abilities. If you got +50% multiplier and added to 6% dodge - it will result in 9% dodge.

From that we can conclude — multipliers are not that dangerous overall. If enemies have no abilities, multipliers will do no harm to you. It may become a problem only at high waves 100+, where even slight change can immediately ruin whole run.


Some bonuses are overall very good. Giants — a good way to improve tower stats while not actually causing much trouble. Even if you bump their chance to 100%, it is not a big deal. In fact, having whole mob consisting from giants still allowed me to reach waves 80-90, despite high HP.

Armor reduction. If you give enemy +50% armor reduction, tower dmg will be reduced by 2x times. And to make towers 2 times stronger would require to get whooping +100% tower dmg bonus. It means armor is more valuable bonus and should always stay under 0%.


The thing that ruined all my normal runs was "+% HP regen". This unbeatable bonus has no counters. Enemy life increases each wave, so they regen more and more HP. Even some tiny +0.2% regen can turn into hell. You see, towers have no priorities which player can controll, so they shoot whoever they like. Splitting damage among enemies will ruin run if they all regenerate HP, cus you waste tower power for nothing and there is no way to tell them "attack same target".

The next immediate death bonus is '+% chance for flying enemies to appear'. They are weak and slow early on, but at waves 50+ even a single one can slip through your defense, again, cus towers have no priorities. Eagles can move over barricades, there is no way to stop them.

Healers and Scientists. Yes, those categories aren't much different from flying ones. Having 4 healers together means +80% heal to all enemies around, and again, since we can't focus fire, healers will die somewhere in the middle of wave, giving incredible boosts to already almost dead mob. Scientists in big numbers will simply shut down towers all the time. But even without their abilities, Healers and Scientists are extra bullet sponges, appearing with 100% chance every wave, increasing wave size beyond normal count. And in this Tower Defense game you don't get money for kills.

• 26.11.2021 - guide was created (introduction, list of changes, T-section, Zig-Zag);
  
• 27.11.2021: added Basic Route and Towers Grid;
  
• 28.11.2021: added Doodad Effects (needs expansion);
  
• 30.11.2021: added Sniper Route;
  
• 03.12.2021: merged Basic Route with T-section and Zig-zag, expanded Sniper Route, corrected typos, shortened text a bit, added info to doodad bonuses regarding armor.