Note that Missing No. can be re-rolled into, but can't be re-rolled out of.
The D4 does not remove traits or abilities inherent to a character, i.e. Azazel's Brimstone-like attack, Lilith's Incubus or The Forgotten's bone attack.
Starting items from Challenges will also not be rerolled
Items that grant pickups (like Pyro or A Dollar) do not remove their bonuses when rerolled.
The D4 can grant items that have not yet been unlocked.
The items gained by the D4 count towards the collection page.
Multiple copies of the same item (as generated by Diplopia, the Debug Console, or gathering them from multiple item pools (e.g. Steam Sale from both the Shop and Greed) will each be rerolled into a different item, even though the duplicates are not present on the pause screen.
There is a small chance that D4 will not reroll every item: the game makes a number of attempts to reroll each item, but if they all fail to produce a new item that is available and applicable, the original remains unchanged.
Smelted/Swallowed trinkets (via Marbles, Smelter or Gulp!) will not be rerolled.
Book of Virtues: Removes all of Isaac's wisps and gives him one random wisp for every two items rerolled. Book of Virtues will not be rerolled in the process.
Interactions[ | ]
Car Battery: Instantly re-rolls Isaac's items twice, which doubles the speed at which the item pools are exhausted and transformations are achieved.
Every Cube of Meat produced using Potato Peeler count as an item for rerolling to the D4. Because health usually is not removed in rerolling items this is useful to increase the number of items at the expense of the item pool.
In-game Footage[ | ]
Trivia[ | ]
The image of the D4 that appears on activation is incorrect; it shows the numbers 9, 7, and 8 on the right face of the die, when it should depict numbers consistent with the left face (i.e. 1 at the top, 3 at the front, and 4 at the right).
Gallery[ | ]
3DS The icon of D4 as seen on the lower 3DS screen.
Splash image which appears when D4 is activated.
Bugs[ | ]
Bug!
Previously held items are not removed from the pause menu, which makes it difficult to determine which items Isaac currently has.
Bug!
When D4 is used with a co-op baby present, the baby's sprite will turn into a glitched sprite of Isaac.
Bug!
If Isaac rerolls Schoolbag, he will keep both active items, but if he picks up a new active item it will swap with the one currently selected and the other will disappear.
Bug!
When Schoolbag is rerolled away while another active item is held along D4, the other active item will be dropped on a pedestal. Activating D4 after the other active item is dropped will then reroll D4 itself.
Bug!
An item picked up is assigned the pool of the most recently generated item; usually this has correct results but a difference can be seen, for instance, by killing a boss, entering a Devil Deal that has items and collecting the boss reward after seeing the Devil items. The boss item will be rerolled to a Devil pool item with D4. Items with no item pool (starting items, fixed drops etc.) will always use the item pool of the most recently generated item from an item pool as a result; if no items from item pools were encountered yet, the treasure room pool is used.
Bug!
Items that are rerolled are assigned the pool of the item with the highest item ID. This means one reroll with the D4 will probably go as expected, but further rerolls will be proliferated by items from the pool that had the highest ID before the first reroll.