Gurmag Angler

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)

Bog Elemental

Protection from white
At the beginning of your upkeep, sacrifice Bog Elemental unless you sacrifice a land.

({T}: Add {B} or {G}.)
As Overgrown Tomb enters, you may pay 2 life. If you don't, it enters tapped.

All creatures get -2/-0 until end of turn.

As an additional cost to cast this spell, sacrifice a creature or pay {3}.

{B}, Sacrifice a Swamp: Put a +1/+1 counter on Mire Shade. Activate only as a sorcery.

Target creature gets -1/-1 until end of turn for each Swamp you control.

When Farbog Boneflinger enters, target creature gets -2/-2 until end of turn.

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)