Etrata, the Silencer can't be blocked. Whenever Etrata deals combat damage to a player, exile target creature that player controls and put a hit counter on that card. That player loses the game if they own three or more exiled cards with hit counters on them. Etrata's owner shuffles Etrata into their library.

Deathtouch

Whenever a creature an opponent controls dies, exile it with a hit counter on it. Assassins, Mercenaries, and Rogues you control have deathtouch and "Whenever this creature deals combat damage to a player, you may remove a hit counter from a card that player owns in exile. If you do, draw a card and create two Treasure tokens."

Deathtouch All creatures able to block Ochran Assassin do so.

Deathtouch Other Assassins you control get +1/+1. Whenever a player loses the game, if they were attacked this turn by an Assassin you controlled, you win the game.

{T}: Destroy target tapped creature.

{T}, Exile an Assassin card from your graveyard: Destroy target creature.

{T}: Put a bounty counter on target creature or planeswalker. Activate only as a sorcery. Whenever a creature or planeswalker an opponent controls with a bounty counter on it is dealt damage, destroy it.

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.

Destroy target nonartifact creature.

({T}: Add {B} or {G}.)

({T}: Add {G} or {U}.)

+1: Until your next turn, whenever a creature deals combat damage to Vraska the Unseen, destroy that creature. −3: Destroy target nonland permanent. −7: Create three 1/1 black Assassin creature tokens with "Whenever this creature deals combat damage to a player, that player loses the game."

+2: You may sacrifice another permanent. If you do, you gain 1 life and draw a card. −3: Destroy target nonland permanent with mana value 3 or less. −9: You get an emblem with "Whenever a creature you control deals combat damage to a player, that player loses the game."