Living Death by paying ({3} magic symbol) ({B} magic symbol) ({B} magic symbol) .
Swarm Intelligence triggers, copying
Living Death.
Resolve the copy of
Living Death, exiling all creature cards in all graveyards, then causing each player to sacrifice all creatures they control, then putting all creatures exiled this way onto the battlefield.
Resolve
Living Death, exiling all creature cards in all graveyards, then causing each player to sacrifice all creatures they control, then putting all creatures exiled this way onto the battlefield.
Mnemonic Wall,
Priest of Gix, and
Priest of Urabrask enter the battlefield, triggering their abilities.