Cast Fractured Identity by paying ({3} magic symbol) ({W} magic symbol) ({U} magic symbol) , exiling Lich and causing each opponent to create a token copy of Lich, and lose life equal to their life totals due to Lich's effect.
You cannot lose the game due to having 0 or less life due to Platinum Angel.
Cast Tranquility by paying ({2} magic symbol) ({G} magic symbol) , destroying all enchantments.
Each opponent's Lich triggers, causing them to lose the game.