mtg.wtf

Skeletons you control and other Zombies you control get +1/+1 and have deathtouch.

Grimgrin enters tapped and doesn't untap during your untap step.
Sacrifice another creature: Untap Grimgrin and put a +1/+1 counter on it.
Whenever Grimgrin attacks, destroy target creature defending player controls, then put a +1/+1 counter on Grimgrin.

Whenever this creature or another Zombie enters, all non-Zombie creatures get -1/-1 until end of turn.

{T}: Add {C}.
{B}, {T}: Put target Zombie card from your graveyard on top of your library.

Other Zombie creatures have swampwalk.
Other Zombies have "{B}: Regenerate this permanent."