Bishop

Bishops are stationary enemies that defend other enemies instead of attacking Isaac. If an enemy or boss is within a large distance of one, it will grant them an impenetrable shield.

This shield effect nullifies all damage the player inflicts so usually it's a top priority to defeat all Bishops in the room first; otherwise, the situation may be unwinnable. Fortunately, Bishops can not apply shields to other Bishops.

Trivia

 * The Bishop is currently the only enemy in the game to apply buffs to other enemies.
 * Bishops are one of the only enemies to wear clothing.