Using Only a two colored deck you can use this combo:

1st Card

Name: Putrid Warrior
Cost: 1white, 1black
Type: Creature
Power: 2
Abilty: Whenever putrid warrior deals damage, choose one: All players gain one life; All players lose one life

2nd Card

Name: Soul Link
Cost: 1white, 1black, 1colorless
Type: Enchant Creature
Effect: Whenever enchanted creature deals damage, you gain that much life

Enchant A Putrid Warrior with Soul Link. Attack if has no creatures (card would also work well with fear). Choose all players lose one life. YOu will be 1 life up and they will be three down.

Hey cool a just thought of another Use bloodfire infusion and Soul Link on the same creature and you'll gain a hells alot of life

Scott Wenzler