We Need To Go Deeper!

We Need To Go Deeper! is an activated item.

Effects

Spawns a trapdoor that leads to the next floor upon activation.
- There is a 10% chance the trapdoor will instead lead into a Crawl Space.
- Some tiles will appear with a special graphic (for example grass or a piece of garbage in Basement). Using this item on these tiles will guarantee a Crawl Space. Only one trapdoor to the Crawl Space can be made per floor, as all subsequent uses will guarantee a trapdoor to the next floor.
The item may be used on the Dirt Patches in the Dark Room to dig up a random type of chest.

All Crawl Space trapdoors on a floor lead to the same Crawl Space.
It can be used in Depths II to access Womb even before defeating Mom and gaining the achievement which 'unlocks' the Womb.
If used in Womb II/Utero II/Scarred Womb II, the trapdoor will always lead to Sheol.
Has no effect in the Cathedral, Chest, Sheol, Dark Room, ??? and The Void (no trapdoors of any type will be generated).
It can only create crawl space trapdoors in the Cathedral, Chest, Sheol, Dark Room, ??? The Void, Corpse II, Home, and during the Ascent.
Using the item on the 3 tiles directly horizontal to a door, including Secret Room entrances, will cause the trapdoor to spawn in a random spot next to Isaac instead, making this item an indirect aid to locating Secret Rooms.
- If a special graphic is in these spots, the trapdoor will likely be moved to a spot that won't spawn a Crawl Space.
- Spawning enough trapdoors can cause a trapdoor to spawn in these spots.
This item can be used to destroy rocks if used while Isaac is flying over a rock.
When used on the last floor of a challenge, a trapdoor to the next floor can spawn. If it is entered, Isaac must beat the boss of that floor to spawn the ending trophy.
Trapdoors will not spawn on challenges on floors at the final destination, however certain challenges like Red Redemption may still spawn a trapdoor leading to the next floor.

Book of Virtues: Spawns a skull wisp on the middle ring that shoots bone tears.
Car Battery: In most cases, no extra effect. When used near the entrances to a room, the item can occasionally open 2 trapdoors at once, increasing the chance of opening a Crawl Space.

Bug!	If a trapdoor is spawned inside of a Black Market with this item and is entered, the player is trapped in the Crawl Space unless they go to the next floor.