The artifact count is high, which is the engine, not a coincidence
He only occupies our 8th place because he is a bit expensive, and not every deck can afford to play a creature that costs so much
Adventurer cards aren't instant or sorcery cards while they're in your graveyard

Izzet Guildmage Izzet Guildmage | Illustration by Jim Murray Commander (1) Creature (7) Oliphaunt Automated Artificer Fallaji Archaeologist Ornithopter of Paradise Academy Wall Trinket Mage Murmuring Mystic Instant (31) Brainstorm Consider Dispel Electrickery Fiery Impulse Frost Bite Galvanic Blast Gigadrowse High Tide Intervene Lightning Bolt Opt Skred Arcane Denial Blink of an Eye Counterspell Deprive Dramatic Reversal Fire / Ice Fire Prophecy Impulse Into the Roil Memory Lapse Moment of Truth Muddle the Mixture Negate Radical Idea Think Twice Thrill of Possibility Volcanic Spite Dizzy Spell Sorcery (9) Gitaxian Probe Hard Evidence Lrien Revealed Ponder Preordain Treasure Cruise Cleansing Wildfire Hidden Strings Merchant Scroll Enchantment (1) Artifact (18) Everflowing Chalice Arcum's Astrolabe Moonsnare Prototype Relic of Progenitus Springleaf Drum Arcane Signet Fellwar Stone Izzet Signet Neurok Stealthsuit Sky Diamond Star Compass Bonder's Ornament Honored Heirloom Lantern of Revealing Network Terminal Firemind Vessel Sisay's Ring Ur-Golem's Eye Land (33) Ash Barrens Command Tower Evolving Wilds Great Furnace Izzet Boilerworks Maestros Theater Molten Tributary Mystic Sanctuary Prismari Campus Silverbluff Bridge Snow-Covered Island x17 Snow-Covered Mountain x4 Terramorphic Expanse Volatile Fjord The cycles of Guildmages from the various Ravnica sets have always made for good uncommon commanders

Keruga, the Macrosage is the opposite of Lurrus and fits comfortably in Commander decks that operate outside of mana values one and two
Between the shell microphone, the colorful streaks in her hair, and the eerie green glow surrounding her, she truly embodies an evil musical Sorcerer