Science!

The Motherlode, Excavator

When The Motherlode enters, choose target opponent. You get an amount of {E} (energy counters) equal to the number of nonbasic lands that player controls.
Whenever The Motherlode attacks, you may pay {E}{E}{E}{E}. When you do, destroy target nonbasic land defending player controls, and creatures that player controls without flying can't block this turn.

When The Motherlode, Excavator enters the battlefield, choose target opponent. You get an amount of {E} (energy counters) equal to the number of nonbasic lands that player controls.
Whenever The Motherlode attacks, you may pay {EEEE}. When you do, destroy target nonbasic land defending player controls, and creatures that player controls without flying can't block this turn.

When The Motherlode, Excavator enters the battlefield, choose target opponent. You get an amount of {E} equal to the number of nonbasic lands that player controls.
Whenever The Motherlode attacks, you may pay {EEEE}. When you do, destroy target nonbasic land defending player controls, and creatures that player controls without flying can't block this turn.