HellishCow

Yeah that's probably fair

I'll be honest it's kind of a jank pile atm, but it should be pretty fun

This probably isn't a deck for you then, sorry :(

Banned in Commander unfortunately

Cut Yahenni, manalith and kwende, add legion lieutenant, legion's landing and arvad's blood fast.

I would add a few cards that benefit from you gaining life, cards like archangel of thune, searing meditation or sunbond. Some more removal, a la council's judgment might be nice too. Otherwise, this deck seems great!

Vedalken Engineer?

You need a sac outlet or mirror entity. You can sacrifice them both infinitely to get infinite death/etb triggers, or put infinite mirror entity activations on the stack, with x being 0. Then with blood artist or something similar on the battlefield or in your graveyard, you get infinite death triggers and kill everyone.

In all seriousness though, this deck is one of the more fun Arcum Dagsson deck's I've played against. Mycosynth lattice in merciless eviction from another guy is... brutal, just brutal. May your inexplicably turn myr into piles of metal for many games to come.

What? No Faerie Artisans?!!

Maybe, but...
Summary dismissal is very important in this deck, as it's the best way to deal with marvel early
Censor doesn't do enough late game, even cycling
Baral tends not to do enough, even with all these spells
With Mardu down right now, I like 1+1 Sweltering suns and 1 release in the sideboard
Thing in the Ice is a trap in this kind of deck
Glyph Keeper is a great card, but the extra value my other threats get make them much better
Pull from Tomorrow is my favourite standard card right now, and I just want to play with it. I'll test this and change it if it needs to be changed
I like 26 lands, the deck really needs to get to 6 mana by turn 6, and this is the best way to do that
Overall thanks for the feedback. I'll continue to improve the deck over the next few months, and see what new toys we get in Hour of Devastation.

Definitely adding blood artist, maybe racthet bomb or another

Sibsig Muckdraggers is too expensive for the explained situation. Try Shambling Attendants instead.

This is freaking awesome!

Why do you have all these fetch lands with very few basic lands. It seems pointless to have so many useless lands.

A good idea would be to add four Helix Pinnacle, as even if they manage to kill all your creatures, you can have put 100 tower counters on it turn four and win at the start of turn five.

You may want to run a few cheap blockers or similar (Dragon Fodder etc.) or you could consider Chandra, Pyromaster for her ultimate. Hope this helps!

First of all, why fetch lands? Second, maybe replace future sight with something more useful, like Run Wild or something similar.

He hasn't got Jace's ingenuity because he has a better version in Tidings.

Nice combo. A good idea might be to add a few cards like Palace Familiar for the sake of blocking and card draw.