Dismember

({B/P} can be paid with either {B} or 2 life.)
Target creature gets -5/-5 until end of turn.

Snuff Out

If you control a Swamp, you may pay 4 life rather than pay this spell's mana cost.
Destroy target nonblack creature. It can't be regenerated.

Death's Shadow gets -X/-X, where X is your life total.

Target player reveals their hand. You choose a nonland card from it. That player discards that card. You lose 2 life.

Target player discards two cards at random.

Target player draws two cards and loses 2 life.

At the beginning of your upkeep, discard a card.

Imprint — When Chrome Mox enters, you may exile a nonartifact, nonland card from your hand.
{T}: Add one mana of any of the exiled card's colors.

Return from your graveyard to the battlefield any number of target creature cards that each have a different mana value X or less.

As Agadeem, the Undercrypt enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {B}.

At the beginning of your upkeep, reveal the top card of your library and put that card into your hand. You lose life equal to its mana value.