Oof, long list. Let's get started.
-Zombie cards (
Cryptbreaker,
Gisa and Geralf,
Compelling Deterrence). We do have some hope they'll become usable with AKH though
-
Wharf Infiltrator. Kaladesh killed the Eldritch Moon star (he never was, but come on; Copter the expansion after him?)
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Akoum Firebird. Problems with relocating attacks to planeswalkers make him unplayable - too bad!
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Shaman of the Pack. Why does Elves tribal suck so hard
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Priest of the Blood Rite. Sac the Priest, keep the Demon, recur the Priest from the yard.
I am surprised that ramp died a death it seems. It was rife in acid moss days and the big Eldrazi payoffs. I think the aggro nature of Duels and vehicles pegged it back. There is support though in AKH so we will see. So Eldrazi for me. Probably Oblivion Sower but then I did not use the builds that work well with Eldrazi anyway.
Ramp died not only because they took out Acid-Moss (though it was a big reason). Ramp died because decks suddenly had efficient answers to Ulamog. As in: The best answers to Ulamog pre-SOI were
Blessed Alliance (only worked because of a bug that cancelled the mill trigger),
Suppression Bonds (Reclamation Sage says hi),
Angelic Edict (which you were unable to cast because Ulamog had just blown up your manabase) or your own Ulamog (The best answer; now your opponent had to deal with this monster and his best answer was exiled).
Can you believe the forum going completely nuts over
Oblivion Strike getting spoiled? Yeah.