To determine the total cost of a spell, start with the mana cost or alternative cost you're paying (such as a flashback cost), add any cost increases (such as kicker costs), then apply any cost reductions (such as that of The Darkness Crystal's first ability)
This deck, though, really gets me excited
Currently, there are only 19 listings for surge foil copies of Lightning, Army of One on TCGplayer, and that low supply isnt surprising given its origins
Also, avoid benching Squawkabilly ex if possible, as its an easy target for Scream Tail
Just do your best with the cards in your collection, make sure you say thanks even if you lose, and if all else fails, maybe you can play the regular tabletop game instead
particularly if you have an Energy card to replace the one used