In variants like Duel Commander, you may have two partner commanders, but only cast one per game
I think the price tag associated with its lack of meaningful reprints goes a long way towards making this staple a very salt-inducing card
Whether you're opening boosters or tracking down singles, these are the 16 most valuable cards from the Through the Ages collection right now

Commander (1) Creature (16) Academy Rector Champions of Minas Tirith Darien, King of Kjeldor Dread Gisela, Blade of Goldnight Kambal, Consul of Allocation Kazuul, Tyrant of the Cliffs Master of Cruelties Royal Assassin Selfless Squire Sheoldred, Whispering One Skyline Despot Suspicious Bookcase Teysa, Envoy of Ghosts Vampire Hexmage Xantcha, Sleeper Agent Instant (15) Anguished Unmaking Batwing Brume Boros Charm Comeuppance Dawn Charm Deflecting Palm Enlightened Tutor Mana Tithe Path to Exile Rakdos Charm Reverberate Swords to Plowshares Teferi's Protection Utter End Vampiric Tutor Sorcery (6) Choice of Damnations Demonic Tutor Fumigate Martial Coup Merciless Eviction Phyrexian Rebirth Enchantment (16) Assemble the Legion Authority of the Consuls Blind Obedience Court of Embereth Delaying Shield Ghostly Prison Land Tax Marchesa's Decree No Mercy Oath of Eorl Phyrexian Unlife Price of Knowledge Revenge of Ravens Solemnity Stolen Strategy Underworld Connections Artifact (11) Boros Signet Chromatic Lantern Commander's Sphere Elbrus, the Binding Blade Forcefield Mirage Mirror Orzhov Signet Rakdos Signet Sol Ring Sunforger Thaumatic Compass Land (35) Arid Mesa Blood Crypt Bloodstained Mire Clifftop Retreat Command Tower Dragonskull Summit Exotic Orchard Fetid Heath Godless Shrine Graven Cairns Isolated Chapel Luxury Suite Marsh Flats Maze of Ith Mountain x3 Nomad Outpost Path of Ancestry Plains x3 Reliquary Tower Rogue's Passage Sacred Foundry Scavenger Grounds Shattered Landscape Shinka, the Bloodsoaked Keep Swamp x3 Temple of Malice Temple of Silence Temple of Triumph Temple of the False God The deck plays Queen Marchesa as its commander and uses a pseudo-pillow fort game style

I may have to send mine in after the holidays (I dont want it to get lost in transit with all the holiday mail)