Mountainous Sword

You may cast pay {2}{r} to cast this. If you do,
attach it to a mountain you control.
Whenever a creature with 5 power or greater
enters the battlefield under your control, you
may sacrifice the land Mountainous Sword is
attached to and attach it to that creature.
Equipped creature has +20/+20 and
mountainwalk.
> Equip {7}