Swamp Lurker

Menace
For 2 life, you may cast this card using another
player's basic green lands, tap them.
{x}: Where X is at least 10 green lands under your control, Regenerate Swamp Lurker, for each extra place a decay counter on a creature you control.
{t}, {2}: Once, you may search your library for one
basic black and one basic green land, target player chooses which you keep, shuffle the
other into your library.