[+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."
Each Assassin token’s triggered ability will trigger whenever it deals combat damage to any player, including you.
If an effect creates a copy of one of the Assassin creature tokens, the copy will also have the triggered ability.