Kethis, the Hidden Hand dominated Standard for a very short window when the 4-color combo deck using Diligent Excavator and Mox Amber was discovered. These cards have now rotated (and now seems to be a relevant combo deck in Modern), but we can use Kethis in a different way in the new Throne of Eldraine format: as a very efficient ramp spell! There are still plenty of excellent Legendary cards that we would want to cast in the Abzan colors, and Kethis is still an overpowered 3-mana 3/4 that can sometimes provide a lot of value in addition to its cost reduction ability.
Abzan Legends with Garruk, Cursed Huntsman
4 Kethis, the Hidden Hand 3 Garruk, Cursed Huntsman 3 Tolsimir, Friend to Wolves 4 Oath of Kaya 1 Liliana, Dreadhorde General 3 Vraska, Golgari Queen 3 Questing Beast 4 Murderous Rider 4 Paradise Druid 4 Incubation Druid 2 Trostani Discordant 4 Godless Shrine 4 Overgrown Tomb 4 Temple Garden 4 Temple of Malady 4 Temple of Silence 2 Forest (347) 2 Swamp (339) 1 Plains (331)
These two cards in combination are the main draw to play a deck like this. Imagine a curve as simple as Kethis into turn 4 Tolsimir, Friend to Wolves into turn 5 Garruk, Cursed Huntsman. You can immediately generate a ton of value, cleaning out your opponent's board and threatening to ultimate Garruk immediately.
Trostani Discordant and Liliana, Dreadhorde General have already proven their power level, and they're even better when they cost 1 less mana. A new application for Trostani could include taking back control of any permanents switched by your opponent's Oko, Thief of Crowns. Questing Beast is a quite powerful new legendary creature, but early testing indicates that it is quite strong. It has so many keywords that it would be hard for at least some of them not to be relevant. It's a great fit in this midrange type of deck, letting us pressure our opponent's life total and planeswalkers at the same time.
It's possible that our removal suite is a bit too clunky, but they're just so individually powerful that we want to try it like this. Oath of Kaya is incredibly strong when it's two mana due to Kethis and can legend-rule itself and subsequently be recast from the graveyard. Murderous Rider is the hot new card in any deck that can produce black mana, so we're happy to prevent our opponents from ever having access to big creatures or planeswalkers.
We have to be able to cast all these big spells if the Kethis plan doesn't come together (and these help even if we do have it), so Paradise Druid and Incubation Druid round out the deck. Paradise Druid allows us to guarantee casting a 4-drop a turn early, while Incubation Druid contributes to our midrange gameplan of every card being able to hold its own as a threat in the mid to late game.
In this particular list we've focused on Kethis and the Legendary package, but another way to go with this type of shell is to focus more on the wolf synergies. Wicked Wolf is a very powerful new card if we are able to include a bit more food interaction such as Gilded Goose. Nightpack Ambusher could replace any of the noncreature 4-drops, and then we can run some number of Once Upon a Time since all of our most powerful cards besides Garruk are creatures. We're excited to start testing this archetype and discovering the optimal build!