THE COMBO 

The deck primarily functions like a control deck, but features the combo of casting Day’s Undoing while Narset or Hullbreacher are on the battlefield.  The end result is the opponent’s hand and graveyard will be shuffled into their library and will draw only a single card while you draw seven.

DAY’S UNDOING 

HULLBREACHER

NARSET, PARTER OF VEILS

The upside of playing the combo is to have a proactive plan against linear decks.  Many linear decks draw cards with Griselbrand or Brainstorm making the draw prevention particularly effective.

Uro was once a consideration to be banned in Legacy, but is now rarely seen because Narset’s static is so oppressive in control mirrors.  When a card like Narset is popular, players will adapt by playing fewer cards it punishes. 

THE SPELLS

NARSET, PARTER OF VEILS

The best way to churn through your deck and the reason the strategy exists.  Once you -2 Narset twice the opponent must respect the static ability as it can lose them the game combined with Day’s Undoing.  It’s nice the -2 ability can find the Day’s Undoing.

Six lands on the battlefield means you can cast both Narset and Day’s Undoing on the same turn if you’re unable to protect it for a turn cycle. 

HULLBREACHER 

The distant fifth copy of Narset for the Day’s Undoing combo.  Hullbreacher is significantly weaker than Narset in most games because it can’t find the Day’s Undoing.  Some lists play two copies.  The 3/2 body can come in handy. 

DAY’S UNDOING 

Remember to take all of your game actions before you cast the card as it will end your turn.  I sideboard out Day’s Undoing against Izzet and Jeskai shells as it’s more difficult to combo once Pyroblast enters the equation.  

Day’s Undoing shuffling graveyards back means I don’t need as many cards that actually kill the opponent.  If The Wandering Emperor dies it can be redrawn after the combo is executed.

TEFERI, TIME RAVALER 

The +1 ability allows you to cast Day’s Undoing on your opponent’s draw step so they won’t get any cards while Narset is on the battlefield. I prefer four copies of Teferi because it allows for more chances to resolve Day’s Undoing to put the opponent in an unwinnable position.

 SNAPCASTER MAGE

This is finally the last of the three-drops.  A 2/1 that is able to close the game once you’re far ahead and can be reset with Teferi’s -3 ability.  I’ve seen versions of Day’s Undoing with Mystic Sanctuary, but I prefer to save that land for decks playing Expressive Iteration.  The strongest cards in this deck are permanents.

SWORDS TO PLOWSHARES

The best white card in the format.  It’s important to have interaction leading up to the third turn to protect Narset. 

PRISMATIC ENDING 

Another powerful white card that interacts ahead of planeswalkers entering the battlefield.  There aren’t any red cards in the main deck, but some matchups require a third color for Ending.  

 BRAINSTORM 

Every Legacy deck plays Brainstorm differently.  Ideally I don’t cast Brainstorm until there is at least one card I want to put back alongside a fetch land.  I will cast Brainstorm more aggressively if I don’t have a third land or a powerful planeswalker to play on turn three.  

Don’t EVER board out Brainstorm!

PONDER 

I cast Ponder more aggressively than Brainstorm.  Its primary function in the deck is to ensure you draw three lands and powerful planeswalkers early in the game.  

SUPREME VERDICT 

Additional creature removal that can be pitched for Forces.  Helps against Izzet Delver, Elves, and Death & Taxes.  Sylvan Safekeeper out of Selesnya Depths can also cause headaches without a main deck sweeper.  

THE WANDERING EMPEROR 

Dodges Pyroblast against mirrors and Izzet Delver.  The creature tokens are resilient and capable of closing the game after Day’s Undoing effectively wins. 

FORCE OF WILL 

Interaction to be cast ahead of three drops.  I like Forces in the mirror because Narset and Teferi must be stopped.  

FORCE OF NEGATION 

Frequently boarded out against decks where Swords to Plowshares shines.  I don’t want to play three Force of Negation because Flusterstorms in the sideboard will suffice.

DRESS DOWN 

Another card to buy back with Teferi’s -3 ability.  Dress Down costs less than three mana and is versatile so it gets the nod. 

THE SIDEBOARD 

The sideboard options for Jeskai decks have historically been powerful and it’s no different here.  

SURGICAL EXTRACTION 

Reanimator is a fine matchup, but youneed to win the post board games.  It’s also a matchup where you need to mulligan aggressively to find cheap interaction and Surgical is at the top of the list.  Free interaction is much better than costing mana as it can be cast through a revealed Chancellor of the Annex.  Narset can also find a Surgical on the third turn. 

SERENITY 

Meltdown is reserved for decks without access to white mana.  I’m able to kill Urza’s Saga and Kappa Cannoneer.  This is the ultimate hammer for the matchup.

PYROCLASM 

I’ve seen Jeskai decks play Kozilek’s Return in this slot, but I don’t want another three-drop.  The upside of Kozilek’s Return, outside of it being an instant, is the colorless damage evades protection from Mother of Runes.  Strong against Death & Taxes, Elves, and 8-Cast.

PYROBLAST 

RED ELEMENTAL BLAST 

A split plays around Surgical Extraction and I won’t have situations where I need to fire off a REB without a target as I don’t play Monastery Mentor.  I don’t want four of these effects because of the red mana requirement.

A consideration for three Pyroblast is a savvy opponent could deduce there isn’t a Monastery Mentor in your sideboard once you show Red Elemental Blast as it can’t be fired off without a target.

HYDROBLAST

Hydroblast overperforms in all of my Jeskai sideboards.  The floor is a blue piece of cardboard to pitch for Force of Will which comes up when you want to board out Swords to Plowshares and Prismatic Ending.  It counters Pyroblast in post board games and plenty of linear decks play red.

RUINATION 

I’ve tried From the Ashes in this slot, but I didn’t like giving my opponent basics when it’s supposed to be the hammer in the matchup.  This comes up most frequently against Mono Green Ramp decks.

Blood Moon can be answered by Boseiju, Who Endures.  This is awkward because most land-based strategies play green and have Blood Moon on their radar.  It also can’t be casually boarded in because you can’t fetch after Brainstorm.

Ruination can be used to destroy Boseiju, Who Shelters All as a last ditch effort against Sneak and Show.

FLUSTERSTORM 

I’ve tried Spell Pierce, but it doesn’t scale and games are expected to go long.  Teferi and Prismatic Ending can interact with cards like Chalice of the Void, Defense Grid, and Blood Moon should they resolve.

SEVINNE’S RECLAMATION 

This is a hammer against Jeskai mirrors and Izzet Delver.  I swap Day’s Undoing for Reclamation in these matchups as it’s hard to resolve the combo in the face of Pyroblast.  

I like Reclamation as the Jeskai mirror haymaker because it doesn’t get hit by Swords to Plowshares or Pyroblast.  Don’t play less than two of this card.

Legacy is in a great place despite Izzet Delver being prevalent.  Give this deck a try or use this information to beat your next Jeskai opponent as it’s a popular choice at the moment.

Thanks for reading!

-Kyle