Jinx

Flash
Cast Jinx only if there are two spells with the same
name cast by two different players on the stack.
When Jinx enters the battlefield choose a player. Whenever chosen player casts a spell, or activates an ability that isn't a mana ability, Jinx deals 2 damage to that player.
{0}, say chosen players name: Exile Jinx. Any player except the chosen player may activate this ability.