ReaperAndross

Yeah, Spider Spawning is too expensive for this deck and doesn't outright win the game when played. It'd be great for an EDH version of this deck though!

And Caustic Caterpillar seems like a good SB option, but I don't know how prevalent artifacts or enchantments are in Modern atm. The only deck that I really know of being super prevalent is Rakdos Scam.

Not that well known, apparently. And the important part was "how I think it does", which yes. It does.

Just putting it out there, that bit when making a deck labelled [DESCRIPTION] is great for this sort of thing!

IF it works how I think it does, then I would recommend a way to either have Grape Shot or Brain Freeze in there as either an alternate or backup to Impact Tremors.

Might want to include cards like Slip Out the Back or Planar Incursion, as they pair really nicely with cards like Fury.
Yeah, I know that this isn't a Scam deck, but it is a really strong combo to consider!

If I had to pick a card to replace in this instance, I'd say Release to the Wind. Yeah, it's only a flicker instead of full exile, but it's cheaper.

That's a great idea! I'll take out Phyrexian Arena for it, since I could just let more things die to Blitz and draw cards that way.

Thanks, mate!
I find personally that a good description actually helps people understand your decks more easily by explaining the thought process. Back when I was known as s0rinmark0v and made by anti-token token deck, I doubt many people would have understood why I included Illness in the Ranks as it is anti-synergy with Tokens, so having that in there really helped people understand the vision!

I see what you did there.
Nice.

Huh. I missed that banning.
I mostly play Commander these days.

So, looking at this deck, I can kinda see why you're interested in using Skred as your big finisher. Issue I have in general is that it is a slow process in mono-red, as you have no ways of actually searching out lands and putting them onto the battlefield quickly enough to really ramp that Skred damage, besides an actual land.
BUT without changing your entire deck to Red/Green and rebuilding it as a ramp deck, here's some notes on the cards you're not a fan of:

Karn, the Great Creator - This card is not great for your deck, unless you're heavily relying on that -2 to fetch cards from your sideboard. But if you wanted to really abuse that passive, add in the card Mycosynth Lattice! It literally shuts down your opponent since EVERYTHING is now an artifact, and your opponent cannot use them. If I had to pick a card to replace from the SB, I'd have to go with Walking Ballista. Yeah, it's an absolutely devastating finisher, but that requires you to have already ramped heaps.

Boros Reckoner - It's a decent deterrent tool, like Phyrexian Obliterator. I think it's fine in any sort of burn deck.

Chandra, Acolyte of Flame - She's actually a good fit for your deck! If the goal besides Skred is red Superfriends, comboing with Sarkhan to give everyone more counters, I'd run more of her! I'd drop a Mind Stone and maybe a Relic of Progenitus to add another copy or two of her. It's always a good idea to have a backup plan, because if you use an early Skred, or it's countered, and someone has a card like Surgical Extraction, there goes your entire deck.

Koth of the Hammer - I know that you didn't mention this one, but I think it needed mentioning. If you swamp Hammer for Fire of the Resistance, then it'll add more of that ramp to find more snow lands. Same mana cost, but fetches lands instead of transforming them, so they can't be killed off like a creature and fuel Skred faster too! Just worth considering. Ult/Emblem is a side-grade, but main ability is a boost.

Hope that helps!

UPDATE 2:
-Archaeomancer
-House Guildmage
-Exploration
-Mystic Snake
-Garruk Relentless

+Eternal Witness
+Sultai Ascendancy
+Slogurk, the Overslime
+Soul Swallower
+Storrev, Devkarin Lich

Replaced Sidisi, Brood Tyrant with Muldrotha, the Gravetide.

Muldrotha is actually better for this deck as more cards can be recurred from the deck. While the zombie tokens are actually great to combine with cards like Dread Return and Undead Alchemist, I think that Muldrotha recurring ramp and lost cards to unfortunate boardwipes is better. Especially since I keep milling out cards like Honoured Heirloom.
Eternal Witness is replacing Archaeomancer since for one less mana, it swaps purely instant or sorcery for ANY card in grave.
Slogurk takes Exploration's spot as it is not only triggered very quickly by the New Capenna lands and general mill, but can also return said lands to be used again and filter the deck faster!
Sultai Ascendancy is replacing House Guildmage, as I was after a more permanent version of Surveil and the Ascendancy is that in all but name. Same effect, just spelled out in full.
As for Garruk, I just wasn't feeling him. Never got to cast him either as when he did appear, I never even got to cast him due to being too short lands for the longest time without ramp. Probably needed to shuffle the deck a bit better, but still. Same with Mystic Snake. While a counterspell on a creature is great, I have other things that need to be played a lot of the time.

Sidisi was more for colours than actually using her ability and it's also a nice bonus effect. She was also sitting on my table, and I don't own a Muldrotha. As for the cards you've suggested, I don't have any or they're all in other decks! Thassa's Oracle, Jace and even Lab Man are all permanent residents in my Jin-Gitaxias deck. Reanimate is also in my Athreos Aristocrats.

Rejuvenator is actually in here for ramp, same with Seeker's Squire and Scout the Border.
I did mention in the description that the Grifter is also in here until I can obtain a Ledger Shredder. I just happen to have Grifter and it's a recurring source of Connive, unlike all my other Obscura cards. Similar story with House Guildmage too, having that recurring Surveil, as I skipped out on the sets after Khans of Tarkir until Neon Dynasty. Managed to get a few random cards here and there from an event I did in that time from Ravnica, but nothing really outside of that.
Invasion of Arcavios is also in here more for the front side than the back one. It being a tutor allows me to search out very important cards like Living Death or Damnation!

The land situation is an interesting one, because I do have rocks and a lot of my lands search out other lands. 7/30 actually search for other lands, 5 of which target Basics also triggering Bonerattle's Domain ability, and 12/30 of them are dual-colour. I've also found that in Commander, having mana rocks instead of some lands is actually more beneficial since it reduces the likelyhood of finding lands late game and accelerating the game.

I'll look out for some of the cards you've mentioned, though. And if I can track down Muldrotha, I'll swap that in over Sidisi!

UPDATED:
-Dreg Mangler
-Fact or Fiction
-Jungle Hollow
-Thornwood Fall

+Ashiok, Sculptor of Fears
+Undead Alchemist
+Verdant Catacombs
+Misty Rainforest

Dreg Mangler, despite having Scavenge, didn't really fit the deck as well as I initially thought. It was the only Scavenge card in here.
As much as I like the idea of Fact or Fiction, Ashiok seems like a better fit overall.
Jungle Hollow and Thornwood Fall were cut because they are only a Land instead of Land - Forest/Island/Swamp. This makes the Snow Lands, such as Woodland Chasm, searchable with the Fetchlands. "Why not cut some of the Basic Lands instead?" Good question! It's because there are quite a few cards that have synergies or requirements for searching Basic lands and those are also for quickly fixing mana.

Hope this little update is some good insight into my design process!

Main thing I see with this deck is that you have no form of removal, and it seems like you are really reliant on using your Creature Lands in order to stop your opponent's creatures. While you do have cards to play lands from your graveyard, I'd be really careful with them.

There is also the concern of you not having any sort of draw cards or abilities in the deck. Once you play through all your lands, you'll be purely in top-deck mode and that's dangerous.

Other than that, really cool idea and interested to see how it goes!

I'd go with Young Pyromancer over Charmbreaker Devils. While you don't get the spell back, those tokens can really help push damage, and keep down that total CMC!

Thanks for the suggestions! I don't actually own any of those cards, but if I can track them down, I'll try to find room for them.
Well, I have one copy of Propaganda, but that's currently in my Zur deck.

I tend to run a lot of removal within my decks, and there is the very real possibility of the One Land Hand being an absolutely crippling opening. If you're banking on specific creatures remaining on the battlefield, then you either need more ways to protect them than 3 Mask of Avacyn. Swapping out the Mindcranks for something like Counterspell would go a long way to making that a more viable engine, but then the issue of said mana producers does come back into play, since Counterspell is a 2 Blue mana Instant.

Considering your endgame is TWO 5-DROPS, only 18 lands seems a little slow for this deck. Even for a casual format like Kitchen Table. I'd add some mana rocks or even just more lands.
You also seem to be relying on those Empires cards to control the game, and without card draw, you're not going to assemble them in time to deal with a lot of decks. Yeah, Fabricate is good to search them out, but considering you're probably using them for your win-con, having other forms of draw might be useful.

If you wanted to keep such a low mana base though, I'd drop two Stuffy Dolls and two Pariah's Shield, maybe some other artifact stuff and use that to get some more defensive cards in such as counterspells!

I missed one word on a card, amongst thousands that I know since starting back in Avacyn Restored. Maybe tone down the condescension.
If you had just said that is was permanents and I had misread the card, instead of all that explanation, then I might have actually said something like "Oops, all good!" and left it at that.

As for actually reading the cards, you want to cut Cut Down in favour of something like Anguished Unmaking or Utter End. Cut Down is far worse than you think in EDH since it is combined Power and Toughness, meaning that any actual threat that this deck wants to stop won't be dealt by it. That way you also hit powerful artifacts and enchantments, which deck will struggle to. Early game, you could deal with a decent 2/2 at best, but drawing that thing late game is such a dead card it isn't funny.

You can't actually summon in Lurrus in this deck, because its Companion ability requires all your cards in deck to cost 2 or less. You have 10 cards in here that break that, therefore you can't actually get it in from outside the game.

Also, EDH is 99 cards in main. One Commander makes it 100 cards.

I can see a case for either answer, with a Signature Spell being tied to a singular Planeswalker. Partner is such a niche rule in general, and these two are the only Planeswalkers with it. If the rules committee say that's ok, then I'd go with them for now.