Not to be confussed with the ones your mum wears in her hair before bed, but large stone boulders...that roll.
Can move in all directions, look for the tiny chalk arrow on them.

1. Kills the Snake (only if it hits their head)
2. Kills all enemys except Roland
3. Makes Roland go into "Fear mode" on impact
4. Do not roll off each other and will stack up to form a line.
5. Pushed by the Snake (depending on it's direction)
6. Pushed by Lucy
7. Pushed by Yorick
8. Rotated clockwise by the Roller Switch
9. Activates Roller Switches (so it's weird when it happens!)
10.Bounced by a Roller Rebounder (180 rotation really)
11. Explodes Bombs and Fuel Bombs, but not Static Bombs.
12. Activates Level Doors
13. Activates Doorway Switches
14. Rotates Deflectors
15. Moves Footballs
16. Moved by Crushers (and not destroyed)
17. Bursts Bubbles
18. Moves Light Blocks
19. Not indestructable to explosions.
20. Moved by Venom