Basic Strategy
If you have ever piloted or played against a Narset deck, you know the basic strategy is to attack and abuse her triggered ability for extra turns and combat steps until you have wiped out the whole table.
So we will be seen be as a huge threat from start of the game. The problem is that even tough Narsets ability is extremely powerful and could potentially end the game with only one trigger that leads to multiple extra turns and combats, it could also hit lands or unfortunate card combinations all the time, which is why I playing her is best described as playing a slot machine.
The main goal for this built should be, to manipulate the odds of that machine and to make it staple enough, to make it go off a couple times, without getting disrupted by wrathes and counters.
Setting up the machine (Lands, Ramp & Evasion)
Everything in this deck is designed to absue Narstes attack trigger, so the first goal has to be, to get her out as quickly as possible. With 6 CMC this would be at turn 7 if we hit every land drop and by then we also need to have a target to attack without loosing Narset, to get the machine going. This is why we run a total of 11 ramp spells to make sure we can consitetly play Narset between turns 4 and 6. To make sure, that we can actually attack by then, we also play a couple of evasion cards like Reconnaissance, Aqueous Form and Steel of the Godhead. Later in the game we will still be happily ramping, as we will be able to cast the big big splashy spell from our hand, on top of the spells casted from Narsets attack triggers. The mana base needs to be flexible enough to make sure we have all 3 mana colors available by turn 4-6. I kept it really budget, of course there are better dual lands available, if you want to invest the money.
Keep the machine going (Protection & Removal)
This slot machine is a big threat to our opponents and basically a glass canon, as all it needs to be broken, is to counter or remove Narset to make our life miserable. Luckily Narset comes with free hexproof which makes our life a lot easier. Still EDH is a format made for wrath effects, so we run a sh*tload of cards that can protect our precious commander like: Indestructabilty, Phasing and Gift of Immortality next to our Umbras that give her totem armor. If Narset is properly protected our opponents can still blast us off the table with good old combat damage. As Narset will be our only creature on the board, unless she's gotten vigilance, she won't be available to block anything. So to close this up we run cards, that stop our opponents from swinging at us too easily, like: Propaganda, Ghostly Prison and Lightmine Field. As it might take us 10 or more turns to hit the jackpot, we still need to be able to disrupt our opponents until then, therefore we run a solid removal kit. Most impactful are control spells that let us remove our opponents commanders, denying them the option to put them back in the command zone, while also giving us blockers. Those are espacially flexible if they can target permanents like Confiscate or Blatant Thievery. Of course they are expensive in mana and one could argue to swap them for more extra turns and attack phases but I always enjoyed hitting them with Narset or casting them, as it makes the deck more divers and also messes with our opponents.
Maximizing the odds (Extra Turns, Extra Combat, Topdeck & Flexibility)
The moment we actually get to attack we wanna make it count. The first and easiest way to maximize our odds, is to play no creature cards whatsoever! Should be a no brainer but you find a lot of lists online that still run creatures... The goal for each attack is to either hit an extra turn or an extra combat phase which is why we run 10 cards for that. On top of that we want to hit as little lands as possible, to get the maximum value. Therefore we have a big suite of cards to manipulate our top deck with Scroll Rack and Brainstorm as the MVPs. Another strategy to maximize the odds or at least maximize the value we generate from Narset is, to play a lot of very flexible cards. One of the best ways for our opponents to stop the machine, is to counter Narset or our precious extra turn spells (which is possible as we still cast everything Narset digs up). So we we would love to run some counters ourselves. Problem is, that if we hit a counter spell with Narset and nobody plays a spell within our turn it is a dead card. Which is why cards like Insidious Will and Mystic Confluence are so great in this deck, they will can give us value even if we can't counter something at the very moment. Also cards like the Umbras or Legions Initiative are great as they buff Narset while also protecting her. Citadel Siege can boost Narset permanently each (extra) turn while also protect us from the biggest creature threats. Mana rocks that can be sacrificed for card draw like Commander Sphere or Hedron Archive are also great examples for flexibility.
Get the Jackpot (Enhancer & Voltron)
To close the game, we need to hit several extra turns and combat phases. I guess the magic number is 3 truns/attacks in one "trun" that will almost certanly win us the game e.g. To get that we multiply our chances several of instant and sorcery doublers. Those can be divided in two types. Permanent doublers like swarm intelligence and one time doublers like Howl of the horde. Both have strengths and weaknesses. If you hit a one time doubler with Narset and have no extra turn or combat to use it on at this moment, it goes down the drain. On the other hand you can easily cast them from your hand, if you hit an extra turn with Narset. Permanent doublers will stay on the battlefield to give value, even if you hit them without an extra turn available, but are harder to cast from the hand as they are much more expensive. With this strategy you will generate very extensive turns (poor opponents). Still to kill up to 3 oppponents with commander damage we would need 21 swings and no defense if Narset hast it's natural 3 power. So we're wise to run cards that buff Narset like Citadel Siege, Argentum Armor, Mammoth Umbra and Drake Umbra.
