Thassa's Oracle in hand or in your graveyard or in your library.
You have a way to draw a card.
({3} magic symbol) ({U} magic symbol) ({U} magic symbol) ({B} magic symbol) plus an additional ({2} magic symbol) ({U} magic symbol) ({B} magic symbol) available if Thassa's Oracle is not in hand, or an additional ({U} magic symbol) ({U} magic symbol) otherwise available.
Steps
Activate The Scarab God by paying ({2} magic symbol) ({U} magic symbol) ({B} magic symbol) , exiling Mirror-Mad Phantasm and creating a copy of it, except it's a 4/4 black Zombie.
Activate the Mirror-Mad Phantasm token by paying ({1} magic symbol) ({U} magic symbol) , shuffling it into your library, revealing all cards in your library and putting them into your graveyard.
If Thassa's Oracle is not in your hand, activate The Scarab God by paying ({2} magic symbol) ({U} magic symbol) ({B} magic symbol) , exiling Thassa's Oracle and creating a copy of it, except it's a 4/4 black Zombie.
If Thassa's Oracle is in your hand, cast it by paying ({U} magic symbol) ({U} magic symbol) .
Thassa's Oracle enters the battlefield, causing you to win the game.