Moonlit Stalker's a key piece in a Harpy tribal deck that, like green-blue Warriors, probably doesn't have the pieces to be viable. On the note of Harpies, Gravelocked Seeker's a really cool design for one or two mana more than I'd be willing to spend on it. Haunted Sunseeker feels like it'd be good in a Persevere deck, but I haven't been particularly happy with that archetype in the past and don't think it's gotten enough support to push it to playability. Planar Eviction is one of the three new Oblivion Rings MSEM2 is getting in this update (along with DYA's Harsh Unpreparedness and PFP's Judge's Decree), and although it's the only one of the three that lacks flash, I think it's still the strongest of them. On the other hand, Oblivion Ring/Banishing Light/Detention Sphere don't see much modern play, so I'm not confident we'll be seeing any of them. Gift of Eternity is another piece of redundancy for decks that want to make themselves unable to lose, then deal themselves massive amounts of damage in a single turn; I'm hoping PFP's All or Nothing brings more such decks into the format. It also allows you to casually tank a Witchpult, so there's that. United Force should see play in RW tokens, and Yrodu is a nonsense card that's probably unplayable but I can't look away from it. Idyllic Tutor will make enchantment tutoring even more readily available, although they're already the most conveniently tutorable nonland card type in MSEM2.
Thunderstride probably has a home in UR spells, at least in builds with a heavier top-end. Two Slippery Capuchins can pass a spell back and forth forever, gaining a limitless number of Surging Kalak triggers each, then swinging unblockably for the kill. Dodgy Infant can substitute for one or both of them, too. Cloudshaper and Sylph Spawning are probably playable in U/X skies; strictly speaking, Breeze Sylph is another Flying Men functional reprint, but not one that deck needs. Synapstorm and OPO's Spilling Secrets make any blue spell a cantrip. Infinite Dreams is an EDH card if there ever was one. Eldritch Undoing is a very narrow answer, but might see sideboard play; Reconsider is essentially Miscalculation, and is thus at least somewhat playable. Vaporize will replace Essence Scatter in 1-2 color control decks, if any are playing it, but I think I like Soul Pierce better in that slot. Aerolius is a disgusting hatebear, but costs one mana too much to be playable. (At U less, would she be a hatedrake?) Orria Mirrorpelt is too stylish not to build an MSEDH deck around. Monkeyshines is a playable cantrip only in decks that want a lot of one-mana cantrips.
Dreameater's sideboard material against control and some combo decks. Deathmask Dancer should see play in base-black aggro decks. Doomsower's cool, but probably costs 1 too much to be playable, at least not without a way to create Human tokens. Deathmask Initiation is a reason for the persevere deck to run black, and a mildly inefficient draw-engine in any black deck with creatures; I don't think it'll see competitive play. Blood Ritual's yet another Lava Spike, this one at instant speed and unable to hit planeswalkers; black-red burn will play it, probably. Blood Bond goes infinite with False Savior or Tharyen, Lord of Subturgia. Path to Mortality would be good at one mana less, but is hard to justify as-is. Birth of Death is expensive, but will see play if mono-black control materializes, and might in UB. Deceitful Tutor should see a little play, replacing Tharyen's Machinations in any deck that currently runs it.
Coralkeeper might see play in RW tokens. Schoolstrider and the UR Merfolk deck in general have potential. Shoring Naiad might be playable in UR spells, if not for the existence of (even post-nerf) Vedalken Reshaper. Naiad Looter's another almost-playable or barely-playable. Impetuous Impetus could be a curve-topper for Sligh decks but I think there are better options. Devious Naiad's a sufficiently stupid combat trick that it might see play in Taiyohata Champion decks. Blood Tide is playable, and in combination with Rylei Wavebreaker might be exactly what Big Red needs to become a real deck. Earthrend has potential, but I'm having a hard time evaluating it.
Alpha Stag's a good curvetopper. Spellbane Vulpine is good against the current spell-heavy meta. Lotusworn Druid would be a key storm card for two mana, but is alas unplayable at four. Springcaller has potential in a GU control deck. Master of the Glen is playable in SOR's Elemental tribal deck, if it ever gets off the ground. Whispers of the Dark is not a good enough engine to be worth the hoops you have to jump through to get it online, which is sad because I'd enjoy jumping through them. Primal Resurgence should be playable. Dying Wishes has potential, but I'm not sure if it'll see play. If mono-green ramp still exists as a deck after the Rock//Roll nerf, Terra Novea has a place in it. Life Immemorial is weaker than Green Sun's Zenith, but not by much, and probably playable even without a Dryad Arbor in the format.
Seila, the Lost One feels close to playable, but not quite there. Not All Who Wander isn't Tooth and Nail, but it's the Tooth and Nail we deserve. I haven't a clue what to run it in, though. Gim-Chimya the Invisible, assuming its rules work, is an excellent wit support card, as well as a generally passable tempo or draw-go threat. Too Clever By Half might surpass Entelan Erasure to be the best wheel in the format. Lotusheart Goran might go in the Abzan Rock deck I've been musing about. Mele is a very strange five-color commander, but probably unplayable in MSEM proper. The Sun Also Rises is one of our better boardwipes, but is confusingly similarly named to The Sun Rises. This Too Shall Pass probably isn't playable, but I'm not certain.
If you've read my PFP review, you know I wasn't excited about its artifact suite, other than a combo enabler or two. I'd like to apologize to Herzi; having not yet examined Novea, I did not understand what an unexciting collection of artifacts looked like. Novea brings us a cycle of enemy-colored mana rocks, and that's it. No equipment, nothing. Gorran Totem might see play in WB lifegain decks featuring Nyatt, Ishyn's Tie, and all of them will find homes in EDH decks endlessly hungry for more manarocks. That's it, though.
Much like PFP, Novea brings a new cycle of full-art basic lands. These I expect to see fairly often, and occasionally use myself; I think the Mountain and Forest are especially pretty.
The nonbasic lands in Novea fall into two monocolored cycles; there's no manafixing for us here. The common cycle are fairly ordinary utility lands; Bloodriver and Corpsebed are probably the most useful, but Seedshrine might also be playable, especially given its synergy with PFP's persist cards. Corpsebed is notably fetchable at instant speed, to snipe cards out of graveyards in response to reanimation; for that reason, I'd venture to say it's on par with Bojuka Bog despite only taking two cards.
The rare cycle of legendary lands are wild. I'm genuinely unsure how to feel about them. The green one's a one-shot mana doubler, the blue one's a wheel, the red one chunks half of someone's life total, the white one's a mass pump, and the black one reanimates someone's entire graveyard. I suspect that Sea of Skies Beyond and Cradle of Corruption, at least, are playable in control decks, and all five of them should see EDH play.
White: Planar Eviction
Blue: Slippery Capuchin
Black: Blood Ritual
Red: Blood Tide
Green: Life Immemorial
Multicolor: Not All Who Wander
Artifact: Gorran Totem
Land: Cradle of Corruption
Command Zone: Orria Mirrorpelt