Gyro

A Gyro is a new type of enemy introduced in The Binding of Isaac: Antibirth. It resembles a living wheel of ham-like meat with a bone sticking out on both ends.

Gyro
Gyros roll around aimlessly. If Isaac gets close, they start rapidly rolling towards him while bouncing off any walls they come to contact with. Their charges are telegraphed by the mass amounts of meat they'll be kicking up behind them as they roll. Often it can be tricky to properly avoid a plethora of charging Gyros as they tend to drift around Isaac if he manages to dodge the first wave.

Gyros will become Grilled Gyros if they touch fire.

Grilled Gyro
Grilled Gyros are a variant of Gyros that leave fire on the ground when rolling. They are created when a normal Gyro interacts with fire. Grilled Gyros can also turn other Gyros into their Grilled variants upon contact.

Grilled Gyros have significantly increased movement speed.