Glowing Hour Glass

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	2 rooms

Glowing Hour Glass is an activated item added in Afterbirth.

Effect[edit | edit source]

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 Joker) do not get restored.
- Score and Time will reset, but about one second will be spent in unskippable animation after use.
- Event counters will get restored (including Donation Machines, Greed Machines, and Eden's Blessing
  +0.7 tears up. Grants a random item at the start of the next run.
  ).

Notes[edit | edit source]

Does not return extra lives.
Using a Joker and then the Glowing Hour Glass to return does not guarantee a Devil Room for every floor as the Joker card does not get refunded. The reason for this is that you immediately change rooms after the Joker card is used, as such reverting to before it was used is impossible.
Does not turn a character back into another should they have been revived by Ankh
Upon death, the player will respawn as ??? with 3 soul hearts.
, Lazarus' Rags
Upon dying, resurrect as Revived Lazarus with one heart container and Anemic item.
, or Judas' Shadow
Adds an extra life; upon death, it respawns Isaac as Black Judas with only two black hearts.
.
- Character changes are reverted by Glowing Hour Glass.

Donations to the Donation Machine or Greed Machine are not reverted, and they can be reset into working state once jammed.
- Other counters not tied to your specific run, such as Slot Machines or Tinted Rocks destroyed, continue to accumulate, allowing easy unlocking of secrets such as the Counterfeit Penny
  Gives a 50% chance of increasing the value of every coin pickup by one.
  , the D4
  Rerolls all of Isaac's items.
  , and Conquest if you have access to infinite uses of the Glowing Hour Glass (see below).
- Event counters are rewinded by the Glowing Hour Glass.
With the Curse of the Blind, Glowing Hour Glass can be used to pick up or purchase an unknown item to see what it is, then decide whether or not to undo picking it up.

Using the Glowing Hour Glass to prevent picking the up while previously having had an active item will return the active item and discharge it completely.

No Damage Achievements are still available if the Glowing Hour Glass is used to reset damage.
Isaac's temporary familiars (blue flies and spiders) duplicate when using the Glowing Hour Glass.
- Fixed.
If combined with The Battery
Activated Items can be "overcharged" to allow for an additional use.
or Sharp Plug
Using an activated item while it's not charged will charge it and Sharp Plug does 2 full heart damage to Isaac.
while blue spiders are present, this combo can generate an infinite army of blue spiders.
The Retro Vision Pill will continue to affect the game even after using the Glowing Hour Glass.
Can be used to unlock multiple achievements tied to the killing of certain bosses such as Mom's Heart / It Lives.
If there is a battery charge in a shop, the Glowing Hour Glass can be used infinitely, by entering the shop without a charge, and using the battery to recharge and exit the shop. This is useful for duplicating temporary familiars or filling up the donation machine, among other uses.
Using the Glowing Hour Glass right after beating Mom's Heart / It Lives / Ultra Greed allows you to get additional Eden tokens.
If a new game is started and Eden begins with this item, using it in the first room will cause the game to crash.

Synergies[edit | edit source]

? Card - Allows for infinite usage as the ? Card gets refunded upon usage.
- The ? Card doesn't get refunded upon usage.
48 Hour Energy pill - Allows for infinite usage as the pill gets refunded upon use.
The Battery
Activated Items can be "overcharged" to allow for an additional use.
- When the item is double charged and used it will also refund the used extra charge bar, making it possible to use it endlessly.
Bum Friend
A portable beggar who follows Isaac, picks up coins for himself, and occasionally drops a pickup after collecting a coin. Does not spawn collectibles.
- 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.
Curse of the Tower
Causes Isaac to spawn 6 troll bombs on the floor every time he gets hit, similar to the Anarchist Cookbook mechanic.
- 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.

Habit
When Isaac is hit, 1 point of an item's charge is filled.
- Allows rooms to be repeated infinitely as long as Isaac has enough health to take two hits, which are refunded on use.
More Options
Two items spawn in every Treasure Room. Only one can be taken; the other will disappear.
- 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.
Sharp Plug
Using an activated item while it's not charged will charge it and Sharp Plug does 2 full heart damage to Isaac.
- Allows for infinite usage as long as you have more than 2 full hearts as the hearts used to charge will be refunded upon use.
Void
Consumes all pedestal items in the room. Active items will have their effects added to Void, and passive items will grant stat upgrades.
- Allows Glowing Hour Glass to be used indefinitely without turning into The Hourglass, although it is impossible to absorb a Glowing Hour Glass pedestal without using the item and preventing it from having been absorbed.