Building NightMaul the right way

Pretty standard stuff for the most part. Game plan is explained in Budget Maul (with mini-guide and explanation) if you're interested.
I'll give you some explanation for my card choices and why I think this is one of the better ways to build the deck.

Transpose market + main deck Maul: Since Maul is the finisher of this deck that you cast and just win, it seems to be the perfect market card. My argument for running it main deck: You want and I mean WANT to draw exactly one of this each game, alright. So you put it in the market with Jennev Merchant, cool. Now you still have 4 draws that give you maul. You've just made maul cost 3 more without adding consistency. But wait, what about also running Great Valley Smuggler? Then you're running 3 cost 2/2s in your deck, a tempo deck that heavily relies on its early game chip damage to make Maul kill the opponent. What's the point of drawing Maul when it doesn't kill the opponent when you cast it? So we're just running it as 4 of in main, yes drawing 3 of them sucks but this is imo the best way to build it (and don't worry that much about drawing the first one, between all the nightfall and Unraveling Fanatic, you'll be drawing cards like there's no tomorrow).

Now to Transpose: This card is GREAT in this deck mainly because of 1 important reason: it pops face aegis. This deck normally doesn't have many ways to push Maul through aegis, but this card enables that, and if it doesn't, it's just 2 face damage; even that's fine for our gameplan. I'd rather have this instead of Jennev Merchant every time.

Market choices:

Cykalis, the Burning Sand: Damage, simple and good. probably the most frequent pick from your market. You can also run 4 Cykalis, the Burning Sand main for more damage and move Albon Roa, of the Order here instead. I prefer Roa in main better and especially like Cykalis in market. Transpose+ Cykalis is 7 surprise damage to win the game.

Xenan Obelisk: The second damage pusher. Pretty good if you have like 3 guys on board, also game winning if you have 8+ max power.

Saber-Tooth Prideleader: Great against relics, great against aggro; you'll take this card a lot of times and feel pretty good playing it.

Turn to Seed: Just got nerfed to 4, I think it's still fine in the market against some weird decks or makto maybe?; just don't be stupid and lose tempo by mistaking it for a normal removal spell, it's not, it doesn't give you tempo. Rain of Frogs is probably better here to be honest.

Tidal Forces: Suggested by OneAntic.
seems to work perfectly with everything this deck is trying to do. If this card ever becomes good, it's in this archetype.

Now to some additional cards:
Initiate of the Sands: I really think you're doing something wrong if you're not running 4 initiates in your nightmaul deck. You're drawing 2 or 3 cards most of your turns so you can almost always use all your power every turn. Just dropping this thing on turn 1 increases your performance by a shit ton. turn 2 3 drop, turn 5 Maul, turn 3 double 2 drop/Albon Roa, of the Order....All these plays are oppressive. Put this in, thank me later.

Unraveling Fanatic: Dies to snowball:( but when he works, he WORKS. He is an extra night effect on his own. if you have a Disciplinary Weights (from Teacher of Humility) on them, his effect gets much better (to be fair that stands for half on this deck) The guy can win the game singlehandedly if left unchecked. I just like the card. It's like the alternative wincon. You can run something else if you don't want your 3 drop to die to snowball and lose the game because of that.

Baying Serasaur: works really well with all parts of our deck. Not that hard to get him to punch for 5 or even 6. Really like this boi, just wanted to mention that.

Final note: This deck is meta dependent (I actually don't know exactly what kind of meta suits this; probably some form of slow control-ish midrange decks with card draw and fat units are the best target because of bounces and Maul) regardless, I really like nightmaul, I've always had, and I'm trying to find the best version of the deck, and I would love to hear about your ideas about improving it. Thanks for reading, hope you enjoyed it, and feedbacks are more than welcome :)