To determine the total cost of a spell, start with the mana cost or alternative cost you're paying (such as an evoke cost), add any cost increases, then apply any cost reductions. The mana value of the spell is determined by only its mana cost, no matter what the total cost to cast that spell was.
Subtlety
The owner of the spell is the one who chooses whether it goes on the top or bottom of their library. All players will know this information.
Subtlety's triggered ability targets a spell on the stack. It can't target creatures or planeswalkers on the battlefield.
Magic: The Gathering · ™ & © Wizards of the Coast · Illus. Svetlin Velinov
Card data via Scryfall. Rarix is fan-made; not endorsed by the rights holders.
