Final Geas [MVP1-ENS29] Secret Rare

If a monster(s) with an original Level of 7 or higher is sent from each player's field to the Graveyard this turn: Banish as many monsters from the Graveyards as possible, then you can Special Summon the 1 highest-Level Spellcaster-Type monster among those banished monsters to your field (your choice, if tied).