Blood Puppy

Spawns a familiar that chases enemies. After killing enough enemies, it becomes more powerful and drops red hearts after killing enemies, but will also try to hurt Isaac. Attacking it returns it to normal.

Quote

"What a cute little thing!"

Effects

• Spawns a familiar that chases nearby enemies and deals 2 contact damage to them per tick (4 per second).
• After killing 15 enemies, Blood Puppy becomes angry, and changes in the following ways:
• • Deals 7.5 damage per tick instead of 2 (15 per second).
  • Gains an attack where it charges at enemies.
  • Drops a half red heart for every 10 enemies it kills.
  • Will also try to attack Isaac, dealing a half heart of contact damage to him.
  • Can swallow bombs dropped by Isaac.
  • Can be damaged by Isaac, returning it to normal after it takes enough damage. Blood Puppy has 20 health and 30 Armor (effective health is ~140-180).
• After getting 25 more kills (40 total), the angry version evolves again, and it has the following modifications:
• • Becomes much larger and deals 15 damage per tick instead of 7.5 (30 per second).
  • Destroys obstacles it runs into while charging.
  • Deals a full heart of damage to Isaac instead of half a heart.
  • Drops a full red heart after every 10 kills instead of a half red heart.
  • Has 50 health instead of 20 (effective health is ~400-500).

Found in

• Curse Room
• Red Chest
• Treasure Room
• Treasure Room (Greed Mode)