Forsake the Worthy, Cast Out, Glory Bound Initiate and maybe Gideon of the Trials are what we got in white.

Sweltering Suns is pretty much all Red got in this set.

Blue and Black have an absolute ton of stuff here.

I think we want to go either Jeskai or Esper with the deck at this point. Slide/Witness hasn't been good enough for awhile now, and things like Shadow of the Grave can replace the CA from the Loam engine while letting the deck work faster.

The biggest single reason for Red is Nahiri, the Harbinger. The second biggest reason is for Faithless Looting. Honestly, it might be worth it to just run those two cards and go four color. Then again, maybe not. Tentatively I'd look at this for a starting point on a list, but this is super rough and off the top of my head, and more about raw power than, like, streamlined playability.

Lands - 23
4x Ash Barrens
2x Irrigated Farmlands
2x Fetid Pools
2x Canyon Slough
4x Polluted Delta
2x Marsh Flats
1x Island
2x Swamp
1x Plains
1x Mountain
1x Underground Sea
1x Tundra

Creatures - 17
4x Bloodghast (maybe Viscera Dragger?)
4x Curator of Mysteries
4x Archfiend of Ifnir
4x Glory Bound Initiate (only good with a Slide in play, probably too cute)
1x Emrakul, the Aeons Torn

Planeswalkers - 4
4x Nahiri, the Harbinger

Sorceries - 7
4x Careful Study
3x Collective Brutality

Instants - 8
4x Shadow of the Grave
4x Force of Will

Enchantments - 5
3x Astral Slide
2x Lightning Rift/Drake's Roost

Hmm, that's 64 cards, and it's super rough, and the mana and CC's are a huge mess, but it's definitely a starting point. Also, no Cast Out, not enough blue cards for FoW.. there's issues, but they're overcomable. I think it needs more discard and counters. Probably some Jace, Vryn's Prodigy too.