Rocks

Blocks movement and projectiles.
Can be destroyed with explosions and certain items like the Notched Axe, The Nail, Leo, or Thunder Thighs.
Can fill in a 1-block wide gap when pushed in the right direction by an explosion, or with one of the abilities that allows destruction by walking onto the rock.
- Note: With these items, it is important to walk in the direction of the gap.
Small chance to reveal a Crawl Space when destroyed.
Destroying 100 rocks will unlock the Lucky Rock trinket.

Tinted Rocks

Sometimes referred to as "Marked Rocks", they are always marked with an "x", and in some levels slightly tinted/discolored. These rocks are much less noticeable in The Womb and Utero due to them being the same color as the surrounding rocks, but can still be distinguished by the "x" on the bottom right.

Destroying 10 Tinted Rocks will unlock Mr. Mega.
Destroying 100 Tinted Rocks will unlock The Small Rock.

Found in: Every Stage

Tinted Rocks have a chance to spawn 1-2 of the following when destroyed:

Soul hearts
Keys
Bombs
Golden chests (only one)
A combination of any of the items mentioned above
The Small Rock (after it is unlocked) (Sometimes spawns with additional pickups, but cannot spawn alongside chests.)

Super Special Rocks

Super Special Rocks are Tinted Rock variants that are much harder to spot, as they have a smaller mark and are not discolored. Super Special Rocks take two bombs to blow up and drop the contents of two Tinted Rocks.

Super Special Rocks are unlocked by Get a 5-win streak, using a different character each time ( this number can be reduced to 3, see the notes section)

Bomb Rocks

File:Bombrock.png

Act like rocks.

Found in: Low chance of replacing any rock.

Bomb rocks can be found anywhere a normal rock can spawn. They can only be destroyed by explosions and "stompy" items, like normal rocks. When they are destroyed, they create an explosion. Note that destroying a bomb rock next to a hole does not create a bridge as with normal rocks.