Dungeon Mobs

Dungeon Mobs spawn inside of Dungeons. They are enemies who range from weak to strong, and must be killed in order to progress through the dungeon floor. Upon death, they have a chance to drop their respective Dungeon gear.

Dungeon Mob Spawning
All Dungeon Mobs spawn only inside Dungeons, whether they spawn naturally or are summoned.

Standard enemies spawn in groups in brown rooms. Some of those enemies will have a yellow star next to their names. When the last mob with a star in the room is killed, it will drop a Wither Key, Blood Key, Blessing, and/or Superboom TNT, as well as marking the room as complete. The more of the Dungeon is explored, the higher the health of the spawned mobs.

All Dungeon Mobs have magic damage resistance: 10% for melee mobs, 30% for ranged mobs, and 50-80% for magic mobs such as Withermancer.

Additionally, each non-boss mob has a small chance to spawn as Flaming, Stormy, Speedy, Fortified or Healthy (e.g. a Healthy Tank Zombie can spawn). Flaming causes the mob's melee attacks to set the victim on fire(the fire isn't negated by Fire Talisman or Fire Resistance potion effect); Stormy lets it strike lightning on nearby players, dealing True Damage; Speedy allows the mob to move much faster; Fortified increases the mob's ; and Healthy increases its maximum. These modifiers may appear and stack with the Runic modifier.

Mobs spawned by The Watcher on Floor 5 and above have some unique modifiers. Boomer makes them drop a block of primed TNT on death, which kills anyone within range instantly, and drop Superboom TNT after the explosion; Golden makes them drop Gold Essence on death; Healthy makes them drop Healing Tissue on death; and Stealthy makes them invisible except for their name tags, armor, and weapons.

Certain mobs, especially bosses and mini-bosses, also have a damage cap mechanic similar to that of the Magma Cube Boss. Any damage it takes above its threshold is reduced by a large amount.

Mini-Bosses
A single Mini-Boss can spawn in certain brown rooms, or alone in the yellow room. Mini-Boss in the yellow room will have increased health and damage.

All mini-bosses except Angry Archaeologist are affected by.

Basic Enemies
All Zombie-type basic enemies can drop Premium Flesh. All non-undead enemies can drop Beating Heart.

The Watcher Undeads
These mobs are spawned by the Watcher in the Blood Room after it is opened. They have high Defense and attack with swords and bows. On floors 2 and above, they gain their respective special perks.

Trivia

 * Skeleton Masters deal a flat amount of, contrary to popular belief that they deal a percentage of their enemies' health. On Catacombs Floor 7, they deal 4000.
 * The highest-health normal Dungeon mob (except Deathmite) is the Zombie Lord.
 * Bats which die of non-player causes (to fire, lava or other mobs) do not grant their secret.
 * Terracotta, Livid and Bonzo had OptiFine capes for a brief period of time.
 * Terracotta had a cape of the transgender flag. Reddit user u/LappySheep purchased the cape.
 * The transgender flag used for the Terracotta was slightly different from the flag used on the Yeti.
 * Livid had a cape of the flag of India. The person responsible is unknown.
 * Bonzo had a cape of the non-binary flag. Player stepsister___ purchased the cape.
 * On February 7, 2021, the capes were removed with a patch.