- King Slime: Takes damage from fire, has 60% damage reduction from other types of damage
- Eye of Cthulhu: Transitions to phase two faster depending on the brightness around it
- World Eater: Head starts shooting Cursed Flames
- Brain of Cthulhu: Blind and confuses the player in first phase
- Queen Bee: Summons aggressive bees to assist
- Skeletron: Summons skeletons to assist
- Wall of Flesh: Upper Eye shoots Ichor Arrows, Lower Eye shoots Cursed Flames
- Queen Slime: Takes damage from fire, has 40% damage reduction from other types of damage
- The Twins: The second Twin gets angry when one is defeated, increasing their stats and gaining buffs for attacks
- Skeletron Prime: When health is below 50%, it gains attack speed
- Plantera: Shoots a volley of petals
- Empress of Light: Inflicts fire damage with her attacks, and reduces flight time upon taking damage
- Duke Fishron: In water, regenerates 0.5% of max health per second, gains +20 defense and +10 attack. While Fishron is alive, players in water get the Suffocation effect
- Lunatic Cultist: Gains increased stats

