I think you might have some dissyergy between Thing in the Ice  ^Flip and Call. I'd try a different finisher that can work independently from that game plan, like AEtherling or some planeswalkers. Have you thought about making this an izzet base so you have access fo Goblin Dark-Dwellers for similar shenanigans?

Red_X, I wish I could but it doesn't work with the goblins. Unlike with brain in a jar, I can't actually cast beck/call fused from my graveyard. The rules regarding fuse state "702.101a: Fuse ... applies while the card with fuse is in a players hand. If a player casts a split card with fuse from his or her hand, the player may choose to cast both halves of that split card... The resulting spell is a fused split spell." So because it's in my gaveyard instead fuse isnt an option. I'll consider the AEtherling suggestion though

But rule 708.6c says "If anything performs a comparison involving multiple characteristics or values of one or more split cards in any zone other than the stack or involving multiple characteristics or values of one or more fused split spells, each characteristic or value is compared separately. If each of the individual comparisons would return a yes answer, the whole comparison returns a yes answer. The individual comparisons may involve different halves of the same split card. " with the example of "Sunforger has an ability that reads, RW,Unattach Sunforger: Search your library for a red or white instant card with converted mana cost 4 or less and cast that card without paying its mana cost. Then shuffle your library. This ability can be used to cast either half of Research/Development, as Research has converted mana cost 2 (even though Development has converted mana cost 5) and Development is red (even though Research is neither red nor white)." I've read elsewhere that this is the same way that dark dwellers works, in that you pick one of the two sides to cast as long as either side fulfills the requirement.

Red_X, the rule you cited only partially applies. What i want to be able to do, is to cast it fused. Goblin dark dwellers would allow me to cast Call in the same way you cast development in your example. So yes I am allowed to cast either side, but not both at the same time. Here is the ruling without the ellipses from my previous comment. I cut out a bit that is relevant here. "702.101a: Fuse is a static ability found on some split cards (see rule 708, Split Cards) that applies while the card with fuse is in a players hand. If a player casts a split card with fuse from his or her hand, the player may choose to cast both halves of that split card. This choice is made before putting the split card with fuse onto the stack. The resulting spell is a fused split spell." Believe me, I want it to work the way you are describing it.

I just realized you never actually said the goblins could cast it fused, my bad. Yes you are right. As you said I could cast either side. I'm just greedy.

Why the one of notion theif? You have no wheels to combo it with, and the decks that care about drawing a bunch of cards a turn (storm, Zooicide) will go off before it hits the board. Plus, it's dead vs. Kikki-chord, affinity, and dredge, among others.

Red_X I do have wheels, Day's Undoing. Trying it out experimentally

My bad, for some reason I thought undoing was one sided.