There are two types of boulder in the current version:
Rock boulders are practically invincible, as they have infinite health, and they are indestructible.
Rubber boulders are destroyable, but they are pretty rare. When they are destroyed, they will drop 2 stacks of hyper rubber.
- Use Yank and Punch ammo to push boulders away.
- In the main servers, they can be a pain in the A$$ if you get trapped with no ammo and no thrusters. They are not a problem in the test servers.