Tick

The Tick is a trinket.

Effects

 * Removes 15% of any enemy's health if they have over 60 HP.
 * Gives Isaac one red heart if he enters an uncleared Boss Room.
 * Once picked up, it can't be removed.
 * The Tick can be replaced by Match Stick.
 * The Tick cannot be replaced with the Match Stick if Isaac has Mom's Purse.
 * The Tick can be removed by Smelter and Gulp!.

Trivia

 * Being able to replace the Tick with Match Stick is a reference of how you can remove a tick that has latched onto your skin in real life with the red hot tip of a match stick; however, removing a tick like this can expose oneself to disease-causing bacteria present in the tick.
 * The Tick is the only trinket that passively changes Isaac's appearance.
 * This trinket is used in Challenge #18 (The Host).