Activate Wall of Blood by paying 1 life, causing it to get +1/+1 until end of turn.
Repeat step 1 until Wall of Blood's power is equal to the highest life total among your opponent.
Activate Jarad by paying ({1} magic symbol) ({B} magic symbol) ({G} magic symbol) and sacrificing Wall of Blood, causing each opponent to lose life equal to Wall of Blood's power.
Each opponent loses the game due to having zero or less life.