Cast Doomsday by paying ({B} magic symbol) ({B} magic symbol) ({B} magic symbol) , searching your library and graveyard for Metallic Mimic, Murderous Redcap, Skirk Prospector, 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 Skirk Prospector into your graveyard and then onto the battlefield.
Activate Grenzo by paying ({2} magic symbol) , putting Murderous Redcap into your graveyard and then onto the battlefield, dealing damage equal to its power to any target.
Activate Skirk Prospector by sacrificing Kiki-Jiki and Murderous Redcap, adding ({R} magic symbol) ({R} magic symbol) .
Murderous Redcap persist ability triggers, holding priority, activate Grenzo by paying ({2} magic symbol) , putting Metallic Mimic into your graveyard and then onto the battlefield, naming "Goblin".
Resolve the Murderous Redcap persist ability, returning it to the battlefield, dealing damage equal to its power to any target.