Rock Balls
 Obstacles 
| ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Rocks and Blocks | Barrels | Poops | Colored Locks | Soot Tag | Lily Pad | Rock Balls | Pipes | Magnifier | Amniotic Sacs | Golden Reward Plate |
Rock Balls are obstacles found in the 
Mines and 
Ashpit. They can be slowly rolled around by walking into them, or shooting at them with Isaac's tears. Rock Balls can also be sent flying with an explosion, and can deal damage to Isaac when colliding with him in this state, until they come to a stop. 
Gritties and 
Marlins can also throw Rock Balls towards Isaac.
Notes
- Rock Balls and their variants behave similarly to and are variants of
Singe's Ball. - Rock Balls will disappear if they are thrown into a pit.
- Some Rock Balls may appear to fall from the ceiling at the start of the room, or until all other enemies have been killed, identical to waiting enemies. They may also break after the room is cleared.
- Singe's Ball has also been given these variants as they can now also appear in regular rooms.
Variants
Lava Rock Ball
Lava Rock Balls behave almost identically to normal Rock Balls, but after being thrown by a Gritty or Marlin it will be destroyed on impact with the ground, and after breaking, it will send 4 lines of fire in the cardinal directions similar to 
Dragon Flies.
Gold Rock Ball
Gold Rock Balls are rare variants of Rock Balls that have a 1/64 chance to replace regular Rock Balls, or appear in some rare rooms. They will drop 3-6 
Coins when broken, and can be broken after being thrown by an enemy, like with Lava Rock Balls.
Gritties will behave differently with Gold Rock Balls — they will ignore them until they are the last remaining option in the room, and upon picking one up, they have a 50/50 chance to either throw it at Isaac or try to fly away with it and leave the room.
Tumbleweed
Tumbleweeds are variants of Rock Balls exclusive to Ashpit. Unlike the other variants, Tumbleweeds will not be able to damage Isaac when sent flying, or after being thrown by a Gritty or Marlin. They are also much lighter than regular Rock Balls, allowing them to be pushed around much easier.
Trivia
- The football spawned from
SOCCER is considered a variant of Rock Ball.