Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature.

Broodbirth Viper

Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
Whenever Broodbirth Viper deals combat damage to a player, you may draw a card.

Dalek Squadron

Menace
Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Demon's Disciple

When Demon's Disciple enters, each player sacrifices a creature or planeswalker.

Butcher of Malakir

Flying
Whenever Butcher of Malakir or another creature you control dies, each opponent sacrifices a creature.

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

Countersquall

Counter target noncreature spell. Its controller loses 2 life.

Riddlekeeper

Whenever a creature attacks you or a planeswalker you control, that creature's controller mills two cards.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Glimpse the Unthinkable

Merciless Executioner

When Merciless Executioner enters, each player sacrifices a creature.

Drown in the Loch

Choose one —
• Counter target spell with mana value less than or equal to the number of cards in its controller's graveyard.
• Destroy target creature with mana value less than or equal to the number of cards in its controller's graveyard.

Oversold Cemetery

At the beginning of your upkeep, if you have four or more creature cards in your graveyard, you may return target creature card from your graveyard to your hand.