One of the best new cards in Dominaria United is actually an old one. It's the return of Liliana Vess, the dark lady of Magic: The Gathering. A healer-turned-necromancer who wears a cursed veil, makes deals with demons, and looks like she knows all the lyrics to Nemesis by Shriekback, Liliana Vess is so goth she shits bats. I mean, her name's an anagram of "a villainess" for goodness' sake.
Liliana has appeared in various guises on different Magic cards over the years, recently cameoing in the university-themed Strixhaven set as a professor of death magic. The Innistrad set introduced a particularly memorable incarnation of her in 2011, and it's this that Dominaria United reprints: Liliana of the Veil, a planeswalker who makes players sacrifice creatures in play and discard cards from their hand. She takes away a summon you've played, then reduces the chance you'll be able to replace it. Which is just mean.
Back in 2011 there weren't many ways to counter Liliana of the Veil. Now there are more options, like Loxodon Smiter in Pioneer format (a big elephant who pops directly onto the battlefield for free if you're forced to discard it), and Tenacious Underdog in Standard (who bounces back out of your graveyard like it's a trampoline), but Liliana is still a solid choice today.
She's been reprinted in the Dominaria United set to fit with its overall retro theme. As part of a celebration of Magic's 30th anniversary it returns to the setting's original plane, and is jam-packed with legendaries. If you open a Collector booster pack there's even a slim chance you might even get a valuable card from 1994's Legends expansion, as some of these ancient cards have been slipped in like Willy Wonka's golden tickets after being discovered in forgotten cases in a closing warehouse.
It's not as powerful a theme as the sets based on twisted fairytales, urban fantasy, cyberpunk Japan, or what if Harry Potter didn't suck, but in my mind Dominaria United's actual theme is "let's make black cards that fucking rule".
Look at Sheoldred, the Apocalypse, a 4/5 legendary who gives you two life whenever you draw a card, and takes two life from opponents when they draw. Evolved Sleeper starts as a one-mana throwaway then powers up as you pump more mana into it, staying relevant in later turns, and several cards interact with your graveyard in fun ways. Urborg Repossession lets you revive creatures back into your hand, and Writhing Necromass is a 5/5 bomb with deathtouch that costs one point less for every creature in your graveyard.
I won a couple of games at a Jumpstart event this week by playing Writhing Necromass early, its cost made cheaper thanks to the pile of dead I'd built up in the early turns—though to give another color its due I survived to that point thanks to the white half of my deck. I guess it's not all about black. Dominaria United gives white plenty of cards with enlist, and a killer Defender called Wingmantle Chaplain I've already had to face a deck built around in Arena. It summons a 1/1 bird for every other Defender you have or play, so my opponent strung together Shield-Wall Sentinels—Defenders that let you search your deck for another Defender to put in your hand when you play them—using each one to find another, growing their bird army at the same time.
Meanwhile, red gets a boost if you're big into goblins—which you obviously should be—thanks to Rundvelt Hordemaster, which gives +1/+1 to other gobbos and a chance to play another goblin when one dies, and Squee, Dubious Monarch, who creates free goblins on attacking. Red also gets Phoenix Chick, one of plenty of flying creatures in Dominaria United—across all colors, not just white who usually gets the lion's share—that has haste and can return from the graveyard with +1/+1. The Phoenix Chick's main advantage may actually be how cute it is, which made me feel real guilty when I cut it down by casting Cut Down in a face-to-face game.
Green's best new cards seem to be ones that pair well with other colors thanks to the Domain keyword, which gives increasing bonuses based on how many different kinds of land you have. Herd Migration gives you a 3/3 beast for each land type, Nishoba Brawler has a power equal to your number of different land types, and Sunbathing Rootwalla (which looks like a frill-necked lizard and I hope runs like one) can spend four mana to temporarily get +1/+1 per land type.
As for blue, nobody cares because it's full of annoying counters and interrupts and only played by cowards and reprobates (pay no attention to the multiple copies of Negate and the new Ertai Resurrected in my deck). Actually, blue does get to make interesting use of the keyword Kicker, which adds effects for extra mana cost. Timely Interference, which gives a creature -1 power, can be kicked to additionally force the weakened creature to block, while Protect the Negotiators counters a spell unless the caster pays extra mana for each creature you control, and can be kicked to give you a 1/1 soldier first, increasing the cost the other player has to pay. Classic blue card shenanigans, but I respect it.
Early in a new set's life sometimes mono-color decks rise to the top as players slowly add to their collections and unlock the best combos and counters. Which has begun already. For instance, Sheoldred, the Apocalypse—a kind of Cenobite centipede woman with a million legs—can be taken out of play with a simple Citizen's Arrest. (If you're having trouble imagining what that would look like, the excellent Twitter account MTG flavor judge drawings has done the hard work.)
There's a lot of potential for things to be shaken up, once somebody figures out a ridiculous interaction involving some of the new cards like Serra Paragon (a white angel who lets you play land or spells that cost 3 or less from your graveyard), or Silverback Elder (a green ape shaman who lets you choose between destroying an artifact/enchantment, playing a land if there's one in the top five cards of your library, or gaining 4 life, every single time you cast a creature spell).
Right now it's time for mono-black to rule, a dark lord on a dark throne. Enjoy this moment while it lasts, swamp-dwellers and death wizards. They'll be coming for your collections of Sisters of Mercy on vinyl soon enough.