Its mechanics tie directly into Tolkiens world: The Ring Tempts You gives your Ring-bearer mounting boons over time, while amassing Orcs floods the board with an Orc army
Depicting one of the more challenging dungeon bosses from Amaurot, The First Beast, this card reminds me of that feeling I had when I first encountered the creepy horned worm with suspiciously human teeth

Bennie Bracks | Commander | Stephen Johnson Commander (1) 1 Bennie Bracks, Zoologist Creatures (18) 1 Alms Collector 1 Angelic Field Marshal 1 Blaring Recruiter 1 Burnished Hart 1 Crested Sunmare 1 Emeria Angel 1 Emeria Shepherd 1 Esper Sentinel 1 Goldmeadow Lookout 1 Keeper of the Accord 1 Lyra Dawnbringer 1 Oreskos Explorer 1 Pentavus 1 Solemn Simulacrum 1 Springjack Shepherd 1 Sun Titan 1 Thopter Squadron 1 Thraben Inspector Instants (20) 1 Angelic Favor 1 Dawn Charm 1 Disenchant 1 Expose Evil 1 Eyes in the Skies 1 Funeral Pyre 1 Generous Gift 1 Holy Day 1 Humble the Brute 1 Path to Exile 1 Recruit the Worthy 1 Release to Memory 1 Return to Dust 1 Rootborn Defenses 1 Settle the Wreckage 1 Spiritual Visit 1 Survive the Night 1 Swords to Plowshares 1 Teferi's Protection 1 Unbreakable Formation Sorceries (6) 1 Entreat the Angels 1 Fumigate 1 Hour of Reckoning 1 Storm Herd 1 Vanquish the Horde 1 Wrath of God Enchantments (11) 1 Cathars' Crusade 1 Court of Grace 1 Darksteel Mutation 1 First Response 1 Land Tax 1 Luminarch Ascension 1 Monologue Tax 1 Pursuit of Knowledge 1 Search the Premises 1 Smothering Tithe 1 Spirit Bonds Artifacts (8) 1 Archaeomancer's Map 1 Extraplanar Lens 1 Mind Stone 1 Pearl Medallion 1 Sol Ring 1 Tamiyo's Journal 1 Thought Vessel 1 Trading Post I do think Bennie Bracks, Zoologist could push up into high power with the right approach, but as you edge towards high power and cEDH you have to start looking at better choices for your commander

Honorable Mentions Legendary Creatures Rubinia Soulsinger seems to be so Commander-friendly that it was even reprinted in Commander 2013
Nuka-Cola Quantum Elixir - An artifact card that provides incredible boosts to your gameplay
He costs more, has less of an impact, and his ultimate, while good, is far from game ending