Delay [Mystery Booster] BW35 Comeuppance deals that much damage

Comeuppance deals that much damage to the source's controller

Then that player loses all unspent mana and you add the mana lost this way

Whenever Oros

Set: Grand Prix Promos Type: Legendary Artifact — Equipment Rarity: Rare Cost: {2} Whenever equipped creature deals combat damage

Ephara isn't a creature

Delay [Mystery Booster] BW35 Comeuppance deals that much damageSet: Mystery Booster Type: Instant Rarity: Uncommon Cost: {1}{U} Counter target spell. If the spell is countered this way, exile it with three time counters on it instead of putting it into its owner's graveyard. If it doesn't have suspend, it gains suspend. (At the beginning of its owner's upkeep, remove a time counter from that card. When the last is removed, the player plays it without paying its mana cost. If it's a creature, it has haste.)