Juggernaut

Juggernaut is a creature type used for large, mercilessly destructive, and unstoppable forces or objects. All Juggernauts are artifact creatures.

The first creature to bear the type was the original Juggernaut in Alpha. Other examples include Mishra's War Machine, Urza's Engine, Keldon Battlewagon, and Phyrexian Juggernaut. Juggernauts typically can't be blocked by walls, attack each turn if able, and/or have trample.

Levelers
are Juggernauts that once each century ripped through every corner of Mirrodin. They were commanded by Memnarch. They killed Glissa's family in one such attack.