Dark Creeping Vines

When a permanent enters the battlefield
with any amount of counters on it, remove
one of those counters from it and put a vine
counter on Dark Creeping Vines.
Creatures with converted mana costs less
than the number of vine counters on Dark
Creeping Vines get -2/-0.
{1}{b/g}{b/g}: Put a vine counter on this card.