Graboid, Great Tremor

Eminence—As long as Graboid, Great Tremor is
in the command zone or on the battlefield, other
Wurm creatures you cast cost {1} less to cast.
Wurms you control have non-basic landwalk.
Whenever a Wurm you control deals combat
damage to a player, destroy target non-basic land
that player controls.
"Hey! Shhhh... Did you hea- WBRG!!"