Circle of Affliction
{1}{B}
Enchantment
As ~this~ enters, choose a color.
Whenever a source of the chosen color deals damage to you, you may pay {1}. If you do, target player loses 1 life and you gain 1 life.
Kalastria Highborn
{B}{B}
Creature -- Vampire Shaman
2/2
Whenever ~this~ or another Vampire you control dies, you may pay {B}. If you do, target player loses 2 life and you gain 2 life.
Sludge Strider
{1}{W}{U}{B}
Artifact Creature -- Insect
3/3
Whenever another artifact you control enters or leaves the battlefield, you may pay {1}. If you do, target player loses 1 life and you gain 1 life.