Cast Doomsday by paying ({B} magic symbol) ({B} magic symbol) ({B} magic symbol) , searching your library and graveyard for one any other card, Zealous Conscripts, Goblin Sledder, Kiki-Jiki, and Priest of Gix, exiling all other cards from your graveyard and library, and then placing the remaining cards on top of your library in the order previously listed and losing half your life, rounded up.
Activate Grenzo by paying ({2} magic symbol) , putting Priest of Gix into your graveyard and then onto the battlefield, adding ({B} magic symbol) ({B} magic symbol) ({B} magic symbol) .
Activate Grenzo by paying ({2} magic symbol) , putting Kiki-Jiki into your graveyard and then onto the battlefield.
Activate Kiki-Jiki by tapping, creating a token copy of Priest of Gix.
Token copy of Priest of Gix entering the battlefield, adding ({B} magic symbol) ({B} magic symbol) ({B} magic symbol) .
Activate Grenzo by paying ({2} magic symbol) , putting Goblin Sledder into your graveyard and then onto the battlefield.
Activate Goblin Sledder by sacrificing it, giving Grenzo +1/+1 until end of turn.
Activate Grenzo by paying ({2} magic symbol) , putting Zealous Conscripts into your graveyard and then onto the battlefield, untapping Kiki-Jiki.
Activate Kiki-Jiki by tapping, creating a token copy of Zealous Conscripts.