Leech

Leech is a passive item.

Effects

 * Upon pickup, spawns a crawling Leech that follows Isaac. If an enemy comes near, the Leech will attack and chase it, dealing 1.5 damage per tick. If an enemy is killed by the Leech, Isaac will be healed by half a heart.

Synergies

 * Arcade Rooms: The player can let the Leech eat flies from the shell game and use the resulting health to gamble on the Blood Bank.
 * E Coli: Enemies can be turned into poop at the cost of half a heart, then consumed by the leech to regain health. Utilization of temporary immunity when hit can allow multiple enemies to be turned into poop, resulting in a net gain of health.
 * Flush!: The leech still is able to attack the enemies turned into poop and gain health.
 * Gnawed Leaf: The player can stand still and allow the Leech to clear a room, granting simple clears and easy health.
 * Chocolate Milk: The leech can consume enemies while the player charges up a shot; so it can be very effective against waves in a Challenge Room due to the fact that 3 waves of enemies must be cleared.

Seeds
M4X7 V0TK (Treasure room adjacent to spawn) (both modes) 3SWF QKD4 (treasure room to the right of spawn) (normal mode only) G4YR 243A (Treasure room adjacent to spawn) L1Y9 Y1KN (Treasure room adjacent to spawn) 2KAD 2W2B (Treasure room adjacent to spawn) YG41 04ZN (Treasure room adjacent to spawn)