Leonin Relic-Warder enters the battlefield, exiling Barren Glory.
Cast Apocalypse by paying ({2} magic symbol) ({R} magic symbol) ({R} magic symbol) ({R} magic symbol) , exiling all permanents and causing you to discard your hand.
Leonin Relic-Warder triggers, returning Barren Glory to the battlefield.
Proceed to your next turn.
At the beginning of your upkeep, Barren Glory triggers, causing you to win the game.