Ok I'm slightly confused... You are running nekusar... And not running Curiosity, Helm of the Ghastlord, Ophidian Eye or Elder Mastery... May I ask why?

Second, Day's Undoing ends the turn as its final effect... And exiles Nekusar, the Mindrazer's damage trigger off the stack, as well as anything that triggered from the people drawing, shuffling, etc.

Additionally, you are missing one of the most damaging combos I know if in nekusar: Bloodchief Ascension+Mindcrank. While this may have something to do with your meta... It's a really solid combo. And lastly... Why no Hive Mind? Basically wins the game if it sticks for a turn

All that being said, this list is probably better than my current nekusar list :/

I apologize for the extremely late response, Entrei. I really need to update the deck description, as it fails to capture what my deck is trying to do.

Many of your suggestions are cards I have tested or tinkered with for a while (especially Curiosity and Helm of the Ghastlord). After extensive testing, I realized that the pain methodology of winning isn't extremely effective. At least, it isn't my cup of tea. I attempted integrating infect, but it wasn't that strong. The effects that were strong were Ultimately, Nekusar himself is a rather predictable and slow strategy, which made me sad.

So, this is a deck that wants to counteract the norm. Nekusar is a figurehead, but little else. I don't usually cast him anymore, unless under some very specific circumstances. This deck wants to win via Laboratory Maniac, using wheels, Notion Thief, and Waste Not as enablers. The Day's Undoing is included as shard reset, in case something goes wrong.

Hope that helps explain some of my card choices.