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| Defeat Delirium as KeeperCrooked Penny|
Crooked Penny is an unlockable activated item added in Afterbirth †.
- Upon use, has a 50% chance to double all items, pickups, and chests in the current room.
- If the effect fails, the items, pickups, and chests disappear, and a penny is spawned.
- If used in a Shop or Devil Room, the duplicated items and pickups can be taken for free.
- If the effect fails in a shop that contains a Restock Box then the Restock Box can be used to refresh the shop, bringing back new items and pickups.
- If used in the Boss Rush room, it can duplicate the items, and all of them can be taken without affecting the originals. Successfully duplicating the items will trigger Boss Rush, and failing to duplicate them will not.
- If used on The PolaroidIf the character has half a red heart or no red hearts after taking damage, it triggers the Book Of Shadows effect, creating a shield that nullifies all types of damage for 5 seconds. Also allows entrance into The Chest. and The NegativeIf the character has half a red heart or no red hearts after taking damage, it triggers The Necronomicon effect, damaging all enemies in the room. Also allows entrance into the Dark Room. after defeating Mom, it can duplicate them, and they can both be taken without affecting the originals.
- The 50% chance is predetermined after each use of Crooked Penny. By force quitting after each failure, this can be exploited to generate large numbers of copies of useful items - if the penny is going to fail, then use it in a different room, recharge it, and try again.
- Car BatteryCauses Isaac's activated item to activate twice on each use.: Activates the item twice, quadrupling all items/drops in the room at a 25% chance. However, if the first activation fails, and the second activation succeeds, a copy of the item will be created as the original disappears, and the new copy will have no cost if it were in a Shop or Devil Room. This has a 25% chance as well, leaving the overall failure chance at 50% (a success followed by a fail will have the same effect as two fails).
See Diplopia#Synergies for info about stacking duplicate items.
- VoidConsumes all pedestal items in the room. Active items will have their effects added to Void, and passive items will grant stat upgrades.: Using Void with Crooked Penny's effect will absorb all items in the room, with a 50% chance to drop a duplicate of them. Note that when one uses Void on Crooked Penny, Crooked Penny may be duplicated and Voided again. Through this method it is possible to gain multiple copies of Crooked Penny's effects, with each copy providing even better average returns per use.
- Glowing Hour GlassWhen used, this item will rewind time, put Isaac back in the previous room, and undo anything that happened in the current room. Any health, pickups, or items gained or lost will be reset back to the previous state.: Glowing Hour Glass can be used to rewind failures. The Crooked Penny can then be used in another room instead, then recharged for another duplication attempt. Schoolbag is helpful for carrying both.
- This item's effect, if the coin flip succeeds, is almost identical to DiplopiaDuplicates all pickups and item pedestals in the room.'s.
- DiplopiaDuplicates all pickups and item pedestals in the room. can be copied by this item.
- Before the first Booster Pack, it could be used on empty item pedestals to cause another item to appear.
PC ZGB7-YX8X (Adjacent to spawn, Treasure Room)
PC C7LV-XHMV (Adjacent to spawn, Treasure Room)