Whenever a creature an opponent controls dies, create a colorless Treasure artifact token with ", Sacrifice this artifact: Add one mana of any color."
At the beginning of your upkeep, if you control ten or more Treasures, you win the game.
9/29/2017 If you don’t control ten Treasures as your upkeep begins, the second ability of Revel in Riches won’t trigger. You can’t take any actions during your turn before your upkeep begins.
9/29/2017 If you don’t control ten Treasures as the second ability of Revel in Riches resolves, you won’t win the game.
9/29/2017 If an opponent’s creature dies at the same time that Revel in Riches is destroyed, you’ll get a Treasure.
9/29/2017 If the second ability of Revel in Riches causes you to win the game, please refrain from throwing your Treasure tokens into the air as this may distract or injure other players.