1B, Sacrifice another creature: Put a +1/+1 counter on Blood Host and you gain 2 life.

Enchant land

Enchanted land has TAP: Target player loses 3 life.

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for 1 or one mana of that creatures color.)

Put target creature card from a graveyard onto the battlefield under your control.

At the beginning of each upkeep, if an opponent lost life last turn, put a +1/+1 counter on target creature you control.

When Gravedigger enters the battlefield, you may return target creature card from your graveyard to your hand.

Whenever a Sliver you control attacks, defending player loses 1 life.

Flying

When Necrogen Scudder enters the battlefield, you lose 3 life.

Nightfire Giant gets +1/+1 as long as you control a Mountain.

4R: Nightfire Giant deals 2 damage to target creature or player.

Other black creatures you control get +1/+1.

2B, TAP: Another target black creature you control gains deathtouch until end of turn. (Any amount of damage it deals to a creature is enough to destroy it.)

Flying

Whenever a creature dealt damage by Sengir Vampire this turn dies, put a +1/+1 counter on Sengir Vampire.