Honestly, my reason to do this is that Seth mentioned this idea on Commander Clash couple of episodes ago and I’ve been thinking about this for a long time, so I decided to do this before Seth could. Not that there’s that much to do here, as most of this stuff just writes itself, although I bet my approach is somewhat different from what anyone else would have done.

Obviously, [scryfall]Yarok, the Desecrated[/scryfall] is commander, but since I do enjoy sabotaging myself in deckbuilding in EDH by coming up with arbitrary limitations to what I’m doing, I’ve also decided to use [scryfall]Umori, the Collector[/scryfall] as the Companion, which means that only lands and creatures in the deck.

Obviously, I’ll put in pretty much all the ninjas. Not actually all, but most of them anyhow. In order to make them work, I have plenty of cheap creatures with evasion. Obviously, I’ve tried to emphasize ones with other abilities as well and most of them do have etb-abilities.

I also have some interaction. There’s some limitations here, since these all need to be creatures, but I didn’t even push that very much. [scryfall]Ravenous Chupacabra[/scryfall] and [scryfall]Cavalier of Night[/scryfall] might be good additions (even with the prohibitive mana requirements of the latter).

Otherwise, there’s some value etb-effects which can often be repeated, as you can always negotiate with others to get opportunities to return them to your hand.

[deck]
[commander]
Yarok, the Desecrated]
[/commander]
[companion]
Umori, the Collector
[/companion]
[ninjas]
1 Throat Slitter
1 Fallen Shinobi
1 Okiba-Gang Shinobi
1 Azra Smokeshaper
1 Yuriko, the Tiger’s Shadow
1 Throatseeker
1 Higure, the Still Wind
1 Ingenious Infiltrator
1 Ninja of the Deep Hours
1 Skullsnatcher
1 Moonblade Shinobi
1 Sakashima’s Student
1 Mistblade Shinobi
1 Walker of Secret Ways
1 Mist-Syndicate Naga
1 Ink-Eyes, Servant of Oni
1 Silent-Blade Oni
[/ninjas]
[evasion]
1 Phantom Ninja
1 Baleful Strix
1 Fogwalker
1 Cloudkin Seer
1 Ice-Fang Coatl
1 Faerie Seer
1 Atris, Oracle of Half-Truths
1 Hypnotic Siren
1 Fathom Feeder
1 Champion of Lambholt
[/evasion]
[interaction]
1 Murderous Rider
1 Big Game Hunter
1 Deceiver Exarch
1 Draining Whelk
1 Deathgorge Scavenger
1 Pestermite
1 Beanstalk Giant
1 Acidic Slime
1 Bane of Progress
1 Deadly Recluse
1 Ambush Viper
[/interaction]
[random etb effects]
1 Champion of Wits
1 Elvish Visionary
1 Burglar Rat
1 Ezuri, Claw of Progress
1 Yarok’s Fenlurker
1 Yarok’s Wavecrasher
1 Mulldrifter
1 Shrieking Drake
1 Keruga, the Macrosage
[/random etb effects]
[ramp]
1 Sylvan Ranger
1 Coiling Oracle
1 Courser of Kruphix
1 Migratory Greathorn
1 Dawntreader Elk
1 Nissa, Vastwood Seer
1 Ranging Raptors
1 Deathcap Cultivator
1 Viridian Emissary
1 Wood Elves
1 Ondu Giant
1 Sakura-Tribe Elder
[/ramp]
[lands]
1 Blooming Marsh
1 Darkwater Catacombs
1 Myriad Landscape
1 Lumbering Falls
1 Botanical Sanctum
1 Sunken Ruins
1 Nurturing Peatland
1 Woodland Cemetery
1 Fabled Passage
1 Ancient Ziggurat
1 Blighted Woodland
1 Darkslick Shores
2 Snow-Covered Swamp
1 Watery Grave
1 Bonders’ Enclave
1 Faerie Conclave
1 Creeping Tar Pit
1 Drowned Catacomb
1 Flooded Grove
1 Waterlogged Grove
1 Prismatic Vista
1 Snow-Covered Island
1 Arch of Orazca
1 Breeding Pool
1 Castle Locthwain
1 Castle Vantress
1 Command Tower
1 Fetid Pools
1 Hinterland Harbor
1 Hissing Quagmire
1 Sunken Hollow
1 Temple of Deceit
1 Temple of Malady
1 Twilight Mire
4 Snow-Covered Forest
1 Zagoth Triome
[/lands]
[/deck]

I might have overdone it just a bit with the ramp and you should probably cut some of the duals in favor of basics, but you’ll never get me to admit that!