Introduction

I started playing EDH when Ikoria came out. I really liked the mutate mechanic and decided to make a 5-color deck based on things having "attacks" - which turned out to become Cromat mutate with all the 2-color charms you could get with almost all the mutate cards. Being a fan of the Pokémon universe for a long time, I decided this would be my "Pokémon"-deck. Of course, I had to buy Pokémon-themed sleeves and all the art cards of the Ikoria monsters were included. The deck was a lot of fun, yet somewhat janky with some cards I really didn't like to play that much (charms, too many tapped lands).
After being introduced to the world of proxies, I create some DIY energy cards with the MTG mana symbols to go with my deck.

This ain't this deck anymore. This is me trying to make a complete Pokémon-themed deck, with trainer cards and whatnot. I won't use only existing cards in the pokemon universe, but instead will have to adapt some, like fetch lands and shock lands etc....
There will be a proxy for every card in the deck, being a card in the old frame of Pokémon cards - that's the frame I grew up with and these are the sets with the Pokémon I like most.
To be fair, most of my experience is based off of playing the video games, not play the trading card game. I collected some cards in my childhood, but I only traded and admired the artwork. So, if someone feels that something is very off with this... it most certainly is.
Knowing some of the short-comings of my older list, I threw in a lot of card draw, as my biggest problem was getting cards in my hand, especially after a wipe. Thus, the section for card acceleration is way bigger than in some of my other decks.

The Decklist

The General Commander

As I said, I started using Cromat as my official commander, as he was one of the 5-color legends that could actually use "attacks". Of course, he's not a very good card, but I did kill someone with commander damage once.... So I call that a win.
Having built an UN-Cube, I got to see the card Surgeon General Commander, a card which came out before mutate even existed. I've seen an alter of this card with the Pokémon-theme, so I needed to build around him. Unfortunately, it's not legal.... Sooooooo I had to have a backup, being Jegantha, the Wellspring (as our lord and savior Arceus).
Surgeon General Commander is great. I've played with him once, and the value he generates is amazing - so amazing. It's that amazing, you don't even need enchanting or the non-legal mechanics to make it a great general for the deck. Also, having Professor Oak be the commander of a deck just makes me happy.

The Pokémon

I tried to fit many of the first 251 Pokémon to these creatures, but I didn't choose the creatures based on existing Pokémon - so some choices are only as close as it gets. I'm more of a gen 2 kid, so many choices will be from that era. Some typing may be off, some of the colors won't fit - please forgive me, I tried my best.

>Basic Pokémon

Having played 5-color mutate with mutate-only-creatures, I knew there wasn't that much need for other cards. This comes from the fact that it's not (only) about creating unblockable/hexproof beaters, but doing fun shenanigans with mutate.
I did however include some of the great minions for any mutate deck to give the deck a little more... Oomph. To note, all of these had to be the base of their respective evolution, as the can't "evolve" by themselves.

• Scute Swarm as Paras. I know, Scute Swarm mutate is kind of hated because of Arena, but it's just that powerful. Turns out copying your valuable stuff again and again can be really really good. Also, I like this card and this deck isn't supposed to be a full meme.
• Trygon Predator as Aerodactyl. In the games, Aerodactyl is a heavy hitter in the air, and this is exactly what this card does. It's removal on a body, gives some kind of evasion and makes a great mutate target.
• Pollywog Symbiote as Poliwag. Seriously, this is a homerun by itself, and a really useful creature on top of it.
• Beast Whisperer as Mr. Mime. He is the only humanoid figure in this deck, so I had to give him this slot. I cast a lot of creatures, and it refilling my hand is something I really want.
• Cold-Eyed Selkie as Wooper. The card on itself is really good if someone already has islands laying around, but mutating on it enhances the card draw ability. Also, Wooper is a good boy and I'm happy to include him.
• Toski, Bearer of Secrets as Pikachu. Hear me out, I needed to include the 'chu himself, but it's not a creature that evolves from a base Pokémon, but rather is one itself. Also, I love Toski and he's legendary and he won't die quickly so Pikachu will hopefully stick around for a while.
• Animar, Soul of Elements as Wobbuffet. Animar is a powerhouse in this deck, reducing costs and becoming a powerful mutate target later on. Wobbuffet is the only Pokémon my mom knows besides Pikachu, and I think it fits the strange vibe Animar is giving off.
• Essence Symbiote as Eevee. I don't like this card that much, but I absolutely had to put Eevee in this deck, as it's my favorite evolution line.
• Crashing Drawbridge INSERT FLAVOR
• Farhaven Elf INSERT FLAVOR
• Wood Elves INSERT FLAVOR

>Evolving

I play all the mutate cards. That's it. While it keeps down the powerlevel quite a bit (not all of these are that powerful), it gives room to the one thing this deck wants: mutate a lot. The good thing about this staff of creatures is them being widely spread on what they do, so there is plenty interaction and recursion. While the choice of creatures is relatively self-explanatory, I will tell you about which Pokémon these are supposed to depict. Many of these are legendary Pokémon, so usually they wouldn't evolve - yet they had to be included, and I couldn't go without them.

• Dirge Bat as Golbat. I love this card, I love this Pokémon, so this was an easy decision.
• Gemrazer as Jolteon. I needed to fit one of my favorite Pokémon, and Gemrazer is one of my favorite mutate cards, so the choice was made.
• Pouncing Shoreshark as Gyarados. I hate that I can't choose Sharpedo for this one, but he's not from the 251, so there is no old artwork for this one.. Maybe I will do this later on, I'll see. But Gyarados is cool too, I guess.
• Sawtusk Demolisher as Rhydon INSERT FLAVOR
• Souvenir Snatcher as Murkrow. He's funny, and he's a black bird.
• Archipelagore as Blastoise. He's a turtle, he's a leviathan, but most importantly, he's on this list watergunning away everything in his way.
• Cavern Whisperer as Sneasel. Being a standalone Pokémon, I usually wouldn't consider Sneasel, but I really like its artwork.
• Chittering Havester as Kabutops. It's slicing, it's dicing, and it's cutting its way to this list.
• Porcuparrot as Moltres. He's a very, very red bird, so I could justify this bad bird creature to be a legendary fire bird.
• Snapdax, Apex of the Hunt as Entei. I like Snapdax a lot, and I think Entei really fits the theme, even though he usually is a dog. Not many dogs in Ikoria.
• Cloudpiercer as Tyranitar. The color and being a big dinosaur matched, so Tyranitar got a slot.
• Mindleecher as Lugia. The two creatures are kind of similar, and Illuna I had to reserve for Articuno, so here we are.
• Vadrok, Apex of Thunder as Zapdos INSERT FLAVOR
• Dreamtail Heron as Articuno INSERT FLAVOR
  as Zapdos. I had to choose between Vadrok and this one, and Vadrok is the way cooler card, so Charizard got that spot.
• Parcelbeast as Suicune. I think they look incredibly alike, so the choice was clear.
• Sea-Dasher Octopus as Tentacruel. Again, this choice is rather obvious.
• Migratory Greathorn as Nidoking INSERT FLAVOR
• Auspicious Starrix as Stantler. He's the only elk, so this had to be it.
• Brokkos, Apex of Forever as Venusaur. I'm a little sad I didn't get this earlier, but Brokkos indeed has plants on his back. Flavor win!
• Cubwarden as Espeon. I had to put it somewhere, and it... kind of fits? Not completely happy with this one, but I'll let it slide for now.
• Everquill Phoenix as Ho-Oh. I wanted to use Ho-Oh for one of the Apexes, but this is the only phoenix, so I had no choice.
• Glowstone Recluse as Ariados. Being the big and bad spider of the 251, he got an invite. I thought about Beedrill, but decided against it for Glowstone Recluse can't fly.
• Huntmaster Liger as Persian INSERT FLAVOR
• Illuna, Apex of Wishes as Charizard INSERT FLAVOR
• Insatiable Hemophage as Gengar. Him being a nightmare really fits to the everlasting nightmares of Gengar, so I'm happy with this choice.
• Majestic Auricorn as Rapidash. Yes, I know, not really the fire-horse, but Girafarig isn't really that cool of a Pokémon, and there aren't that many horses in mutate either...
• Regal Leosaur as Flareon. I needed to put this somewhere, so I chose to use this little fire-kitty as my Flareon-spot.
• Trumpeting Gnarr as Umbreon. While it doesn't necessarily fit the theme 100%, it's still somehow in the colors.
• Vulpikeet as Ninetails INSERT FLAVOR
• Boneyard Lurker as Snorlax. It's totally not on theme in terms of its typing, but I love the idea of Snorlax lurking around anywhere.
• Lore Drakkis as Dragonite. It's not the most potent of creatures, but I like it, and Dragonite, and it had to be in the deck.
• Necropanther as Umbreon. Umbreon is one of my favorite Pokémon, so she had to get a spot on this list.
• Nethroi, Apex of Death as Raikou. It's a kind of weird, kind of yellow cat, so I could definetely use this as a Raikou-replacement.
• Otrimi, the Ever-Playful as Mewto. Otrimi is a powerful beast, and while not the most powerful mutate creature, it's the OG mutate commander, so I wanted to show him some respect. Also I think the card image kind of fits the theme of Mewto.

The Trainer Cards

Everything non-creature and non-land has to be a trainer card. This is mostly ramp and card draw spells, so it is easy to find some cards for those. The artworks were chosen more in a flavor-sense than in a sense of "it has to has the same effect".
Also, kind of by accident, this deck has no instants. This, so I heard, fits the non-instant-interaction nature of the Pokémon TCG, but I swear I didn't plan this when I put together this list.

• Mimic Vat as Poké Ball
• Lightning Greaves as Running Shoes

>Board Wipes

These are tricky, as usually the trainers can't interact with the Pokémon of the other trainers. I had to include some form of interaction though, So I figured it would be fine.

• Nevinyrral's Disk
• Oblivion Stone

>Card Acceleration

• Guardian Project
• Lifecrafter's Bestiary
• Primal Surge
• Reconnaissance Mission
• Season of Growth
• The Great Henge
• Zendikar Resurgent

Coming soon.

>Ramp

• Arcane Signet
• Chromatic Lantern
• Fertile Ground
• Migratory Greathorn
• Sol Ring
• Utopia Sprawl
• Wild Growth

Coming soon.

Energy Cards

While the event of someone taking energy cards as a replacement for lands isn't really a novelty, I only heard of people doing so after wanting to try it myself. The basic lands are easily replaced by the basic energy types, the other lands are somewhat tricky. One has to design several "multi-energy"-cards for the triomes and shocks and some idea for the fetchlands.

Futher thoughs

I had a lot of fun putting the deck together, and will now go into the process of designing the cards (with altered text) to get a hang of how this would look.
Further updates will follow.

• lands: stadium cards
• artifacts: trainer cards
• enchantments: supporter cards