LeaPlath Spider Sorcerer

But that doesn't tell me a direction. Ramping into Bolas early? Grixis midrangey sacrifice stuff? Tempo? Control? This could be a flavourful EDH deck?

16 lands is no where near enough in a deck that goes up to 7 mana, seriously.

I don't see why an aggro deck would run a 4 mana planeswalker, who doesn't contribute to the game plan.

Fathom Seer is basically just divination which sets your mana back 2 turns, not Gush as it wants to be. You also have access to Metallic Mimic now to up the illusion count and be a lord 5-8

I also have many doubts about your sideboard.

So, few issues I can see. First up, something of a lack of focus? Lots of fringe cards mainboard for example, such as Alliance, Deflecting Palm, etc. And the deck itself looks a cross between hate bears, and this reanimation combo which I don't think is all that great? I don't think you need stuff like Doomeds to make the combo work.

Depends, what direction do you want to go?

I'm not sold on 3 pan, given how it is 4 mana and doesn't do anything the turn it comes down. 6 mana, even with Nykthos in a 19 land deck seems iffy. I would cut 3 pan, 2 grave titan, 3 transgress, for 1 IoK, 1 arena, 1 push, 4 lands, and then swap the rats for 3 copies of pack rat.

22 should be the minimum, and more is better. Also your lack of mana dork at 1 mana is concerning. As is your line up of attrition midrange discard/souls, and coco coco+removal+spells as creatures

18 creatures is no where near enough for CoCo. https://www.channelfireball.com/articles/magic-math-orator-of-ojutai-collected-company-and-dragons-of-tarkir/ this goes into pretty good detail on the coco maths

You have 8 instants/sorceries, greatly negating the benefits of Kiln Fiend. Shock should be Lightning Bolt.

Like if this is for legacy, you have better cards for nearly everything, and for a deck called the Azorius Senate, it lacks any much Azorius.

Do you want actual suggestions to improve this?

There are better spells to replace nearly all the ones you have, lands too, and some random high cost outliers who would be better replaces. Sin Prodder is really a Mono Red Lock card, it turns your spells into 1-3 damage, but lets people discard them, as opposed to letting you trade them 1 for 1 for their card and 2 damage.

A control deck needs to be able to go 1 for 1 and pull ahead on cards in the mid to late game. This can't do that, because so many of your cards are not netting you card advantage or them card disadvantage? Cards like master just give them more draw steps to break your attempted damage lock. Turn 5-7 is pretty early still given the fastest balls to the wall deck wins on turn 4ish.

This deck is in dire need of focusing? Like, you go shardless or Czech pile, and you want different cards in each? Shardless probably being cheaper.

Leovald is a real must at the moment, due to other leovald decks. And you have DRS and fetches, you don't need noble as well? Cut em for some strixs and 2 more FoW

Path to Exile, and Condemn are seeing a lot of play remember, and Blightsteel Colossus at least ends it in 1.

Emrakul, the Aeons Torn or Emrakul, the Promised End wins in 2 and is also pretty protected. Given how your big turn 4-5 play is make a 5/5, that seems very weak?

Fair enough, consider Defy Death in place of one of the 4 manas, or Unburial Rites.

Also, you can cut about 3 swamps for 3 plains, makes Emeria easier to turn on and mana better.

See, Archfiend is a 5/4 flyer and it rewards you for just normally cycling, as opposed to having to go all in? Like, just being able to threaten that makes it decent when setting up future living ends. Like, you never want to go "vomit my hand" because it leaves you with nothing, and one of the benefits of Living End is the random fringe cards it can constantly cycle into.

So. I'm guessing you don't know much about tournament magic, so if I explain something you do know, sorry.

Legacy is a very low to the ground format, with most spells in the format that see play costing 1-3. This is because of how efficient the various cards can be. Delver of Secrets  ^Flip is a 1 mana 3/2 flyer who applies pressure for just building a deck that has a high density of spells. Stoneforge Mystic lets you create an uncounterable 4/4 vigilance lifelinker for 2 mana, return it to hand, and replay it for 2 mana, while also thinning your deck by 1 card. Brainstorm, Force of Will, Wasteland and Swords to Plowshares are all staples of this format.

From a basic deck building standpoint, 22 lands, turn 4 fixing and no dual lands in a deck that wants to cast heavy mana cost cards (ie wanting to have UU on turn 2, 1BB or UBR on turn 3) is going to struggle to both find and play the land to cast cards on curve, and have the correct mana.

If you take this to a legacy tournament, you will get mullered. A lot of these cards are better off in commander, than a competitive format.

If you just want to play this in casual, that is fine, I've got some suggestions for that. If you want to play this is competitive, then it is unlikely, but I can suggest stuff.

So what makes Sphinx of the Final Word better than say...Emrakul or Progenitus?

So when will you need to dump your hand like that, when a board with 4-5 4/4s, 6/4s, 5/4s and 3/4s not be enough?