I started noting down which bosses were immune to what, and then figured I might as well make a guide out of it so you don't have to throw away tiny lives in vain. It's fun to explore and discover for yourself though, so please consider this guide more of a reminder of monster stats. Some numbers are bound to be wrong due to me miscalculating the DMG, or killing the the monsters before they had time to do all their abilities etc. I am unlikely to chart everything as I am a lazy wight, but hopefully it'll offer some guidance. Let me where I've missed stuff and I'll do my okayest to rectify it.

• Slime 15 HP, SPIT ACID at 1 Folk: POISON, STICKY GOO at 1 Folk: -2 DEF
  
• Hornet 10 HP, STING 1 Folk, MOVE FORWARD
  
• Slime small, STICKY GOO at 1 Folk: -2 DEF
  
• Mushroom 20 HP IMMUNE POISON, SPORE 1 Folk: 5 DMG, POISON GAZ several Folk: POISON
  
• Bear 15 HP, BITE 1 Folk: 5 DMG, ROAR at 1 Folk: -2 ATK

BOSS: Ent 40 HP, BURN WEAK

• CUT 1 Folk: 5 DMG & BLEED,
  
• WHIP 1 Folk: 5 DMG

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• Ogre 30 HP, ROAR at 1 Folk: - 2ATK, TRAMPLE 2 Folk: 10 DMG
  
• Rat 5 HP, BITE 1 Folk: 5 DMG
  
• Cyclop 50 HP, TRAMPLE 2 Folk: 10 DMG, ATTACK 1 Folk: 20 DMG
  
• Goblin 25 HP, THROW SPEAR at 1 Folk: 5 DMG

BOSS: Goblin King 60 HP

• THROW SPEAR at 1 Folk: 5 DMG
  
• ATTACK 1 Folk: 20 DMG
  
• SLASH 1 folk: 10 DMG

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• Ram 25 HP, CHARGE 2 Folk: 5 DMG
  
• Chicken 10 HP, SLASH 1 Folk: 5 DMG, PECK 1 Folk: 2 DMG
  
• Scarecrow 30 HP, BURN WEAK, IMMUNE POISON/BLEED, SCARE 1 Folk: -2 ATK,
  
• Rooster 15 HP, SLASH 1 Folk: 5 DMG
  
• Pig 25 HP, HEADBUTT 1 Folk: 10 DMG
  
• Hornet 10 HP, STING, MOVE FORWARD
  
• Frog 15 HP

BOSS: Bull 70 HP

• IMPALE 1 Folk: 5 DMG & Bleed,
  
• DRAWN TO BLOOD: 10 DMG

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• Skeleton 30 HP, IMMUNE BLEED, THROW BONE at 1 Folk: 15 DMG, ATTACK 1 Folk: 20 DMG,
  
• Snake 40 HP, BITE 1 Folk: 5 DMG & POISON, CONSTRICT 1 Folk: 10 DMG & -2 DMG & -2 DEF
  
• Ram 25 HP, CHARGE 2 Folk: 5 DMG, HEADBUTT 1 Folk: ? DMG
  
• Djinn 40 HP, FIREBALL multiple Folk: BURN,
  
• Scorpion 35 HP, PINCH 1 Folk: 10 DMG,

BOSS: Vulture 150 HP

• BREATH FIRE at 3 Folks: 10 DMG & BURN
  
• BITE 1 Folk: 20 DMG
  
• SLASH 1 Folk: 10 DMG

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• Ghost 30 HP IMMUNE BLEED, Become ETHEREAL: +3 DEF, SCARY THOUGHT at 1 Folk: 20 DMG
  
• Will O 25 HP, IMMUNE BURN, Become ETHEREAL: +3 DEF, BURN 1 Folk: 5 DMG & BURN
  
• Zombie 50 HP, IMMUNE POISON, SLASH 1 Folk: 5 DMG, BITE 1 Folk: 5 DMG/POISON/Heal Zombie, BARF at 2 Folk: POISON
  
• Skeleton 30 HP, IMMUNE BLEED, ATTACK 1 Folk: 20 DMG
  
• Banshee 80 HP IMMUNE BLEED

BOSS: Dead Spirit 200 HP, IMMUNE BLEED, SCAR PSYCHE 1 Folk: 20 DMG

• KNOCKBACK 1 Folk: 10 DMG
  
• THROW Tomato at 1 Folk: 10 DMG & -2 ATK
  
• BURN 3 folk: 5 DMG & BURN

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• Brute 50 HP, STRIKE 1 Folk: 30 DMG, ATTACK 1 Folk: 10 DMG, HEADBUTT 1 Folk: 15 DMG
  
• Plague Doctor 30 HP, POISON GAS all Folk: POISON, POISON SYRINGE 1 Folk: 20 DMG & POISON, SUMMON LEECH, HEAL self
  
• Leech 25 HP, CONSTRICT 1 Folk: 10 DMG/-2 ATK/-2 DEF
  
• Zombie 50 HP, IMMUNE POISON, SLASH 1 Folk: 5 DMG, BITE 1 Folk: 5 DMG/POISON/Heal Zombie, BARF at 2 Folk: POISON
  
• Witch 60 HP, CURSE 1 Folk: 5 DMG/-3 ATK, GIVE POTION: random buff/debuff to ally
  
• Pig 25 HP, HEADBUTT 1 Folk: 10 DMG
  
• Hobbo 40 HP, SUMMON RAT, DRINK: Heal self for 20 HP

BOSS: Mecanix 250 HP, IMMUNE POISON/BLEED, BURN WEAK

• SHOOT 1 Folk: 10 DMG
  
• RELEASE STEAM: Self -5 DEF & +5 ATK
  
• STRIKE 2 Folk: 10 DMG

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• Hornet 10 HP, STING 1 Folk: 10 DMG & POISON
  
• Fly trap 40 HP, BITE 1 Folk 10 DMG & POISON, STICKY GOO 1 Folk: -2DEF
  
• Crocodile 80 HP, BITE 1 Folk: 20 DMG, WHIP 1 Folk: 15 DMG
  
• Mushroom 20 HP IMMUNE POISON, RELEASE SPORES at 2 Folk: POISON
  
• Leech 25 HP, CONSTRICT 1 Folk: 10 DMG/-2 ATK/-2 DEF
  
• Turtle 110 HP, BITE 1 Folk: 20 DMG,
  
• Slime big 45 HP, SPLASH ACID at 3 Folk: 5 DMG
  
• Zombie 50 HP, IMMUNE POISON, SLASH 1 Folk: 5 DMG, BITE 1 Folk: 5 DMG/POISON/Heal Zombie, BARF at 2 Folk: POISON
  

BOSS: Giant Leech 250 HP

• ABSORB 1 Folk: 5 DMG & Heal 5 HP
  
• BITE 1 Folk: 5 DMG & BLEED or POISON or Heal self 10 HP

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• Leech 30 HP, BITE 1 Folk: 10 DMG & BLEED, BECOME SLIPPERY: self +1 DEF, ABSORB 1 Folk: 5 DMG & Heal 5 HP
  
• Poseidon 50 HP, IMMUNE BURN, TSUNAMI at all folk: 10 DMG ignore DEF,
  
• Fishman 45 HP, IMMUNE BURN, STING 1 Folk: 5 DMG & POISON
  
• Eel 30 HP IMMUNE BURN, ZAP 1 Folk: STUN,

BOSS: Linnworm 150 HP IMMUNE BURN

• GROW HEAD: Heal 25 HP
  
• BITE 1 Folk: 30 DMG

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• Miner 50 HP, PICKAXE 1 Folk: 15 DMG, FLASH 1 Folk: STUN, RUMBLE all Folk: 10 DMG
  
• Slime big 45 HP, SPLASH ACID at 3 Folk: 5 DMG, STICKY GOO 1 Folk: -2 DEF
  
• Slime small 5 HP, STICKY GOO 1 Folk: -2 DEF, SPIT ACID at 1 Folk: 5 DMG, GROWS into Slime
  
• Slime 15 HP,
  
• Spider 35 HP, WEB 1 Folk: -3 ATK, BITE 1 Folk: 20 DMG
  
• Kreaper 30 HP, SELF DESTRUCT at all Folk: 15 DMG

BOSS: Mole 200 HP

• PICKAXE 1 Folk: 15 DMG
  
• SLASH 1 Folk: 5 DMG
  
• DIG: summon Column 40 HP & become untargetable.
  
• EARTHQUAKE: 10 DMG to all Folk
  
• RUMBLE all Folk: 10 DMG

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BOSS: PRISM 250 HP IMMUNE POISON/BURN/BLEED

• SHOOT RAY at 3 Folk
  
• RAY 1 Folk: BURN
  

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• Ogre 30 HP, ROAR at 1 Folk: -2 ATK
  
• Ghost 30 HP, Immune Bleed
  
• Spider 35 HP, WEB 1 Folk: -3 ATK, BITE 1 Folk: 15 DMG
  
• Bear 15 HP, SLASH 1 Folk: 10 DMG
  
• Yeti 80 HP, ATTACK 1 Folk: 15 DMG, BITE 1 Folk: 20 DMG

BOSS: Spider Queen 300 HP, Immune Poison

• POISON 1 Folk: 10 DMG & POISON
  
• WEB 1 Folk: STUN
  
• BITE 1 Folk: 25 DMG

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• Crab 90 HP, PINCH för 24 HP
  
• Sea Urchin 20 HP, STING 1 Folk: 10 DMG & POISON, THROW SPIKE at 1 Folk: 10 DMG
  
• Hermit Crab 130 HP, PINCH 1 Folk: 15 DMG, HIDE self: +5 DEF
  
• Octopus 80 HP, THROW SPEAR at 1 Folk: 20 DMG
  
• Pirate 60 HP, BACKSTAB 1 Folk: 15 DMG, ATTACK 1 Folk 15 DMG

BOSS: Kraken 300 HP, Immune Burn

• BITE 1 Folk: 30 DMG
  
• DIVE, summons two Tentacles with 50 HP & become untargetable,
  
• SMASH 2 Folk: 15 DMG

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• Mimic 80HP, BITE for 20 HP, SOLIDIFY: +5 DEF
  
• Dark Tentacle 35 HP, HIT 1 Folk: 35 HP
  
• Cyclop 50 HP, TRAMPLE two Folk
  
• Dark Spirit 60 HP, SCAR PSYCHE 1 Folk: 15 HP, SCARE 1 Folk: -2 ATK
  
• Evil Knight 80 HP, ATTACK 1 Folk: 20 HP, STRIKE 1 Folk: 30 HP
  
• Dark Demon 100 HP, HIT 3 Folk: 30DMG, DARK SPELL 1 Folk for 30 HP

BOSS: Dark King 400 HP

• HIT 3 Folk: 30 DMG
  
• Hit 1 Folk 30 DMG
  
• TRANSFORM (Under 50% HP?)
  
• Dark Storm above 1 Folk for 5 DMG
  
• Dark Spell 1 Folk : 30 DMG
  
• TRANSFORM (Under 30%?)
  
• DARK RAY 1 Folk for 40 DMG
  
• BITE 2 Folk: 20 DMG

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