Bonebreaka
Bonebreakas are a type of Heavy Ork tank. Used by all Ork Clans, it is armed with a single heavy Battlecannon in a turret and a huge spiked Deathrolla on its front hull. The spiked Deathrolla is what gives the Bonebreaka its name.
Nowadays it has been mothballed by Games Workshop, possibly because it looks too similar to the Battlefortress and its countless flavors or the Battlewagon without the Deathrolla.