Cast Triumphant Reckoning by paying ({6} magic symbol) ({W} magic symbol) ({W} magic symbol) ({W} magic symbol) , returning all nonland permanents from your graveyard to the battlefield.
Archaeomancer enters the battlefield, returning Triumphant Reckoning from your graveyard to your hand.
Activate Phyrexian Altar seven times by sacrificing Archaeomancer and six other creatures, adding seven ({W} magic symbol) .