In the case of Demonic Covenant the last ability looks for both cards to match card types, the supertypes and subtypes are ignored
Kuja, Genome Sorcerer Kuja, Genome Sorcerer puts a Rakdos spin on what's usually a blue-themed archetype
How Do Red Cards Work in MTG
I also went with the Spellskite maindeck since its good at blocking Wild Nacatl and diverting spells away from Steel Overseer and is incidentally very good against decks like Splinter Twin and Auras

Archipelagore Auspicious Starrix Boneyard Lurker Brokkos, Apex of Forever Brokkos, Apex of Forever Cavern Whisperer Chittering Harvester Cloudpiercer Cubwarden Dirge Bat Dreamtail Heron Everquill Phoenix Everquill Phoenix Gemrazer Gemrazer Glowstone Recluse Huntmaster Liger Huntmaster Liger Illuna, Apex of Wishes Illuna, Apex of Wishes Insatiable Hemophage Lore Drakkis Majestic Auricorn Migratory Greathorn Mindleecher Necropanther Nethroi, Apex of Death Nethroi, Apex of Death Otrimi, the Ever-Playful Parcelbeast Pollywog Symbiote Pollywog Symbiote Porcuparrot Pouncing Shoreshark Regal Leosaur Sawtusk Demolisher Sea-Dasher Octopus Snapdax, Apex of the Hunt Snapdax, Apex of the Hunt Souvenir Snatcher Surgeon General Commander Trumpeting Gnarr Vadrok, Apex of Thunder Vadrok, Apex of Thunder Vulpikeet