Shrine Rooms are special rooms that can be randomly encountered first in any of the Revelations floors. These shrines grant negative floor modifiers in exchange for vanity points; these effects last through the whole chapter. Vanity can be spent in Prank's shop, which appears after defeating the boss on any given second floor.
Bombing an untouched shrine will activate all shrines in the room, plus add an additional random shrine effect (doing this also provides bonus vanity).
Once the player leaves the room, all untouched shrines will deactivate and cannot be interacted with again.
Revelations enemies now have a chance to become champions. Bosses have an increased chance to become champions.
Grounding
Flight is removed for the chapter. This also affects characters who start with flight.
Scarcity
Pickups have a chance to disappear when spawned.
Purgatory
Enemies have a chance to spawn a purgatory ghost on death, which launches at the player and explodes.
Hemorrhage
Red health will drain over time. This effect stops at half a heart.
Mitosis
Enemies have a chance to get doubled when spawned.
Punishment
A random item is removed from the player.
Glacier only
Name
Effect
Mischief
Glacier Prank will appear and wreak havoc in some Glacier rooms by stealing pickups and by other means until defeated. When defeated, Prank will drop bonus pickups and a vanity discount will be granted in the vanity shop.
Frost
The Shrine room becomes a Chill room. Warmth auras are smaller and Grill O' Wisps move faster.
Fragility
The Shrine room's floor becomes entirely coated in ice. Ice pits can crack and break when stepped on, causing Isaac to fall in. Ice Hazards will follow Isaac.
Ice Wraith
A special Chill O' Wisp follows the player between rooms, freezing their head and preventing them from shooting. It will deactivate for a short time after freezing the player.
Tomb only
Name
Effects
Mischief
Tomb Prank will appear and wreak havoc in some Tomb rooms by stealing pickups and by other means until defeated. When defeated, Prank will drop bonus pickups and a vanity discount will be granted in the vanity shop.
Revival
Revival mechanics are more dangerous, and any revival rag can spawn with a revival projectile on top. Necragmancers gain more HP and attempt to revive things faster.
Peril
Traps become more dangerous. Activating traps gives them additional effects depending on the type of trap.
Paranoia
All traps are now labelled with a '?', leaving their effects unknown. Fake traps that do nothing have a chance to spawn.
Shrines were introduced in Chapter 2, and overhauled completely in the Vanity Update.
Prior to the Vanity Update, you were originally forced to take a single pact when encountering the shrine room. Leaving without doing so would force the boss to be a champion.
Pacts offered a bonus positive effect rather than giving vanity.
Pact of Mischief and Frost were originally named Gratuity and Radiance.
Willo is based on one of Pact of Frost's original positive effects.
Maxwell's Horn is based on one of Pact of Peril's original positive effects.
