Glowing Hour Glass

Glowing Hour Glass is an activated item added in The Binding of Isaac: Afterbirth.

Effect

 * Upon usage, Isaac will be returned to the previous room and everything that happened in the current room will be undone.
 * Health, bombs, coins, keys, cards/runes/pills, items, and trinkets will be restored.
 * Certain consumables (such as the ) do not get restored.
 * Score and Time will reset, but about one second will be spent in unskippable animation after use.
 * Completion marks earned in the room will be removed.
 * Event counters will get restored (including Donation Machines, Greed Donation Machines, and ).

Synergies

 * : Allows for infinite usage as the ? Card gets refunded upon usage.
 * Allows for infinite usage in rooms where a lot of damage can be dealt, most notably boss rooms.
 * 48 Hour Energy pill: Allows for infinite usage as the pill gets refunded upon use.
 * : Clearing any room is enough to instantly recharge the hourglass, allowing infinite tries for best outcome.
 * When the item is double charged and used it will also refund the used extra charge bar, making it possible to use it endlessly.
 * Using the Glowing Hour Glass after the Bum Friend has picked up coins but before it has spawned pickups will restore the coins in the room but will still cause the Bum Friend to drop pickups. This can be used to repeatedly generate pickups from the same set of coins.
 * If used quickly after taking damage, Troll bombs will spawn in the previous room. If you have the Safety Scissors, these can be harvested as normal.
 * Using the Glowing Hour Glass after the Dark Bum has picked up hearts but before it has spawned Soul Hearts will restore the hearts in the room but will still cause the Dark Bum to drop Soul Hearts. This can be used to repeatedly generate Soul Hearts from the same set of hearts.
 * Time can be reversed while inside one deal to go into another.
 * + : Using Glowing Hourglass to return to the previous stage will keep the charge Eraser received from entering the next stage.
 * Allows rooms to be repeated infinitely as long as Isaac has enough health to take two ( three) hits, which are refunded on use.
 * Hairpin: If Hairpin is held while entering any Boss Room for the first time, Glowing Hourglass may be used indefinitely on said room to repeat the fight until you beat it.
 * Only applies after Booster Pack 5.
 * If used after entering the Treasure Room for the first time, upon reentering the room, one item will have changed places and another will be new, effectively making More Options a choice of 3 items instead of 2. If used a second time, the items change back.
 * Using the Glowing Hour Glass after retrieving it from Moving Box will not deplete its charge. Allows for infinite usage as long as Moving Box is fully charged.
 * Using the Glowing Hourglass will activate the effect of Saturnus again, essentially allowing for double the amount of orbiting tears, if the player returns to a room, where the tears created by Saturnus were not destroyed.
 * Allows for infinite usage as long as you have more than 2 ( 1.5) full hearts as the hearts used to charge will be refunded upon use.

Interactions

 * The bag's contents will be reverted to its previous state.
 * Any wisps lost in the previous room will be restored, and an additional Glowing Hour Glass wisp will be added.
 * No effect.
 * It is impossible to absorb a Glowing Hour Glass pedestal without using the item and preventing it from having been absorbed.
 * The Glowing Hour Glass is absorbed like normal. Subsequent uses of Void send Isaac back to the previous room reverting most changes, nullifying many other effects that Void may have absorbed. Energy is still reset back to full upon each use, allowing for infinite re-tries of any room. This does, however, prevent you from consuming any further powers as you will instead reset the room.

Trivia

 * Prior to Booster Pack 5, Glowing Hour Glass would turn into after being used 5 times.
 * The icon of Glowing Hour Glass turning into the one of The Hourglass when it's not fully charged may be a nod to that.

Seeds
NDJQ D4GT (First floor Treasure Room) SRVZ MGKQ (First floor Shop, quarter in Treasure Room) Y1WR PKCD (Eden spawn) PFTJ B87Y (Second floor Shop for 7 cents) 36WC YDYT (First floor Treasure Room) 07C6 H920 (Second floor Treasure Room) 3NBT BZ0W (Flooded Caves II Shop) YBW1 J3E0 (Eden Spawn)