I really like this decklist! Props my man!! My only thing is how this would play against aggro, more specifically R/W. With new set out I feel exert and always watching is going to be a thing at my lgs.

So looking at this list my question is what would be the best thing for this! I see counter spells/archfiend/ and maybe sweltering suns but I'd like to think they'd have at least 4 toughness. And grasp for a single target.

Have you play tested against this or something similar?

Exert variants are fairly easy to beat. Aside from Glorybringer, a lot of their stuff dies to almost every removal spell. Usually in those games the priority is getting an Archfiend of Ifnir online as soon as possible. Once I have that it's nearly impossible for them to recover. They also want to curve out so its really easy to Censor them out of a key card. I've managed to play against Exert 4 different times so far and won 3 of my matches.

You might want to keep scarab feast in mind in case any of those b/u control decks run Enigma Drake

Scarab Feast is more for Zombies and Scrapheap Scrounger. Enigma Drake dies to most of my removal so I'm not that worried about it.

Glyph Keeper seems relevant since he is hard to remove and his recursion would help late game

Glyph Keeper has a couple things that I'm not a fan of... Being able to play a Sweltering Suns and keep my Archfiend of Ifnirs and Curator of Mysteries is a very important factor. While it does retain value even when discarded, I don't think its better than my current creatures and I'm very hesitant to cut the kill spells until the meta settles. In these early stages, the one thing that usually works is the kill everything plan. I will keep it in the back of my mind though in case something arises where it would be better than my current cards.

Just so you know, clayperce has been doing some online testing and said he hasn't seen ANY Heart of Kiran.

I'm pretty sure that people won't play many Vehicles at the start of this season as there are too many hate cards.

As a result I think that Artifact hate cards could maybe be not as useful as other stuff in the Sideboard.

Just a thought.

I've still been seeing a decent amount of Mardu Vehicles on XMage... but even if they do drop off By Force is still a decent answer to Torrential Gearhulk and Dynavolt Tower... I'll look into what the best move forward will be and keep that in mind though. Thanks :)