Plunderer's Prize (8)

Mana cost
Mana value	1.0
Type	Sorcery
Rarity	rare
Colors	U

Seek a nonland artifact card with mana value X or less and put it onto the battlefield. If a card with mana value less than X is put onto the battlefield this way, this spell perpetually gains "This spell costs {1} more to cast," then return this spell to its owner's hand.