Bitter Feud
{4}{R}
Enchantment
As ~this~ enters, choose two players.
If a source controlled by one of the chosen players would deal damage to the other chosen player or a permanent that player controls, that source deals double that damage to that player or permanent instead.
Sower of Discord
{4}{B}{B}
Creature -- Demon
6/6
Flying
As ~this~ enters, choose two players.
Whenever damage is dealt to one of the chosen players, the other chosen player also loses that much life.