Doom Blade

Demonic Rising

At the beginning of your end step, if you control exactly one creature, create a 5/5 black Demon creature token with flying.

Tragic Slip

Target creature gets -1/-1 until end of turn.
Morbid — That creature gets -13/-13 until end of turn instead if a creature died this turn.

Murder

Swamp

Pithing Needle

As Pithing Needle enters, choose a card name.
Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.

Desecration Demon

Flying
At the beginning of each combat, any opponent may sacrifice a creature of their choice. If a player does, tap this creature and put a +1/+1 counter on it.

Sign in Blood

Target player draws two cards and loses 2 life.

Tribute to Hunger

Target opponent sacrifices a creature of their choice. You gain life equal to that creature's toughness.

Sever the Bloodline

Exile target creature and all other creatures with the same name as that creature.
Flashback {5}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Liliana of the Dark Realms

+1: Search your library for a Swamp card, reveal it, put it into your hand, then shuffle.
−3: Target creature gets +X/+X or -X/-X until end of turn, where X is the number of Swamps you control.
−6: You get an emblem with "Swamps you control have '{T}: Add {B}{B}{B}{B}.'"

Mutavault

{T}: Add {C}.
{1}: Mutavault becomes a 2/2 creature with all creature types until end of turn. It's still a land.

Mutilate

All creatures get -1/-1 until end of turn for each Swamp you control.

Vampire Nighthawk

Illness in the Ranks

Devour Flesh

Target player sacrifices a creature of their choice, then gains life equal to that creature's toughness.

Disciple of Bolas

When Disciple of Bolas enters, sacrifice another creature. You gain X life and draw X cards, where X is that creature's power.

Geralf's Messenger

Geralf's Messenger enters tapped.
When Geralf's Messenger enters, target opponent loses 2 life.
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Lifebane Zombie

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
When Lifebane Zombie enters, target opponent reveals their hand. You choose a green or white creature card from it and exile that card.

Underworld Connections

Enchant land
Enchanted land has "{T}, Pay 1 life: Draw a card."

Curse of Death's Hold

Enchant player
Creatures enchanted player controls get -1/-1.

Appetite for Brains

Target opponent reveals their hand. You choose a card from it with mana value 4 or greater and exile that card.