Our plan is to use The Elderspell to destroy one or two of our own planeswalkers in order to add enough loyalty counters to The Royal Scions to immediately use their ultimate. Then we use Brought Back to get back our other planeswalkers, and get extra activations from them. If we have a Tamiyo, Collector of Tales with at least 4 loyalty, this sequence gives us two cards back from our graveyard. These can be Elderspell and Brought Back, allowing us to start the process over next turn. Add in activations of Vraska, Golgari Queen or Teferi, Time Raveler and the value becomes pretty hard to compete with.

The most efficient way make this stable is to get The Royal Scions to 6 loyalty, then elderspell exactly one other walker. Since this puts them at exactly 8 loyalty, the ultimate will neatly kill them off, and Brought Back can return both them and the planeswalker you destroyed with The Elderspell. You can then plus them to get them back to 6 loyalty, allowing you to repeat the sequence next turn.

Of course, getting to this point requires that you stick two to three Planeswalkers on the board, and that's pretty hard to do most of the time. Fortunately, Brought Back also helps protect and get value from your walkers before you're ready to use The Elderspell. With 3 Tamiyo in the deck, you don't have to worry about using them early. You'll be able to retrieve them when you need them.

The Mana Base

Because Brought Back is double white, while The Elderspell is double black, we need a strong commitment to Orzhov mana, but those colors by themselves just don't give us the planeswalkers we need to make this strategy work. Fortunately, we have Interplanar Beacon. Between that and our 4 Guild Globe and 4 Golden Egg we can play planeswalkers in all 5 colors.

We do stick to Orzhov colors for everything else though, since this reduces the strain on our one-use-mana-fixing artifacts. Every land in the deck besides Interplanar Beacon taps for either Black or White mana. Thus, if we have Interplanar Beacon then we have the colors for our planeswalkers, and we can use our artifacts to cast cards like Kaya's Wrath, that the beacon makes difficult. And if we don't have the Beacon, then we should only need our artifacts for our walkers.

We're also running a relatively low number of lands at only 21 in the deck. We get away with this through a combination of early draw effects and a reasonably low curve (topping out at four in the mainboard and five if you side in Nicol Bolas, Dragon-God).

Tips & Tricks

If you have a Golden Egg out, and are about to use Brought Back for a single walker, you can sacrifice the egg first, and bring it back as well for an extra card draw. This also works with Guild Globe if you've got a spare mana to make up for the fact that guild globe can't make the double white you need to cast brought back. If you have two mana to spare, you can eat an egg and gain three life.

When playing on MTG Arena, the auto-tapper is not your friend. Our mana costs are very specific, so if you want to play more than one spell in a turn, think it through and tap manually.

If you have a brought back ready to cast, you can use Vraska, Golgari Queen to sacrifice one of your walkers, then bring them back for extra activations.

If your opponent steals your stuff with Mass Manipulation or Agent of Treachery, you can use Brought Back to steal it back if and when it dies.

Vraska, Golgari Queen's emblem can be a secondary win condition, attacking with human tolkens created with Castle Ardenvale. Remember you can give them +2/+0, First Strike, and Trample with The Royal Scions.

When you play an Oath of Kaya while one is already on the battlefield, and the legendary rule kills one, you can bring it back with Brought Back for another trigger.

Keep an eye on the number of cards left in your library. Our main win condition involves hitting our opponent in the face with The Royal Scions' ultimate, but because this also makes us draw 4 cards, and we go through our deck pretty fast in general, we can sometimes end up in a situation where we will mill ourselves before we kill our opponent. Try and recognise that this is happening early, so you can switch gears and go for the Vraska, Golgari Queen emblem kill instead.

Sideboarding

Aggro matchups are probably are probably our biggest issue, given that we typically don't do much until turn 3. Mortify should help us in these kinds of matchups. Even Despark has some applications here, hitting Questing Beast and Embercleave, but you probably don't want all 4.

Mortify also doubles as our only form of enchantment removal, at least for enchantments with Converted Mana Cost above 3 like Fires of Invention or Doom Foretold.

The Wanderer is a surprisingly efficient tool for keeping ourselves alive against any deck running burn spells or large creatures that also feeds into our theme. Of particular note: She hits Questing Beast while also protecting your other planeswalkers from its "damage a planeswalker" ability.

Noxious Grasp is a solid card against any green or white deck, but we esspecially want it if the opponent is running Nissa, Who Shakes the World or Teferi, Time Raveler. If you're wondering why Teferi is of particular concern here, it's because he stops us from playing Brought Back on our opponent's turn, which is surprisingly crippling.

Despark has targets against every major deck in standard right now, but we don't want all 4 of them unless our opponent's deck is particularly high on such targets. Jeskai Fires is the matchup where it is most applicable, hitting both Nightpack Ambusher and Nissa Who Shakes the World means it's probably worthwhile against Simic Flash as well.

Duress helps in any slower control matchup, but it's also really nice against Simic Flash, or other counter heavy decks.

Nicol Bolas, Dragon-God helps power out card advantage in slower matchups. It also gives us an extra backup win condition against decks that might use Unmoored Ego to cut The Scions out of our deck. Unmoored ego is still pretty scary because it can take The Elderspell, but in slower matchups you can still win without that just by protecting your planeswalkers and grinding out value. At least, so long as you still have a win condition in the deck.

Against faster decks you can typically trim a Tamiyo, Collector of Tales and/or a The Royal Scions. This will mean it takes longer to assemble your combo and get the elderspell train rolling, but both of these planeswalkers are low tempo plays, and you don't need them clogging up your hand early game.

Kaya's Wrath and Oath of Kaya are pretty dead against non-creature based matchups, which gives us a lot of room to sideboard in these matchups.

You're going to be tempted to remove Guild Globes and Golden Eggs. Don't. We badly need all of them, both for mana fixing, and just to make our land drops. Our high odds of being able to draw an extra card on turn 2 is part of what lets us play such a low land count, and without our little artifacts we will be mana screwed more often than not.

Known Issues

Graveyard hate is really effective against this deck. Ashiok, Dream Render isn't that bad due to the fact that he provides fuel for The Elderspell, and can't stop Brought Back, but things like Leyline of the Void can completely shut us down. Return to Nature is also surprisingly anoying because the of "Exile a card from a graveyard" mode shutting down both Tamiyo, Collector of Tales and Brought Back.

The deck really struggles against heavy aggro. Our mana base is mostly shock lands, and typically we won't have a strong play until turn 3-4. That's not to say we can't win, but game one in particular is an uphill battle.

Final Thoughts

This is a goofy deck that's way more consistant and powerful than it has any right to be. It's going to be a bit too slow and grindy for some, but if you like a deck with complex moving parts, sequencing puzzles, and huge late game potential, then give this a shot.