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Crypt Cobra
{3}{B}
Creature -- Snake
3/3
Whenever ~this~ attacks and isn't blocked, defending player gets a poison counter. (A player with ten or more poison counters loses the game.)

Suq'Ata Assassin
{1}{B}{B}
Creature -- Human Assassin
1/1
Fear (~this~ can't be blocked except by artifact creatures and/or black creatures.)
Whenever ~this~ attacks and isn't blocked, defending player gets a poison counter. (A player with ten or more poison counters loses the game.)

Swamp Mosquito
{1}{B}
Creature -- Insect
0/1
Flying
Whenever ~this~ attacks and isn't blocked, defending player gets a poison counter. (A player with ten or more poison counters loses the game.)