Darksteel Mutation is a Commander favorite that reduces even the scariest threat into a harmless 0/1 insect with no abilities
Does Commander have a sideboard
its a sweeper, a planeswalker, and it closes the game fast
Like how my Sultai article showed how synergistic that combination's color combinations are, looking at Raffine's top commanders will reveal just how much Esper loves both looting (drawing and discarding cards) and picking creatures out of the graveyard and returning them to play

Gandalf, Friend of the Shire | Commander | Mark Wischkaemper Commander (1) 1 Gandalf, Friend of the Shire Creatures (3) 1 Acquisition Octopus 1 Archaeomender 1 Mischievous Catgeist Enchantments (14) 1 Aether Tunnel 1 Aqueous Form 1 Auramancer's Guise 1 Cloak of Invisibility 1 Combat Research 1 Curiosity 1 Curious Obsession 1 Drake Umbra 1 Eldrazi Conscription 1 Flight of Fancy 1 Octopus Umbra 1 Security Bypass 1 Take Flight 1 Tricks of the Trade Artifacts (42) 1 Arcane Signet 1 Argentum Armor 1 Batterskull 1 Brass Knuckles 1 Chariot of Victory 1 Diviner's Wand 1 Ebony Fly 1 Goggles of Night 1 Grappling Hook 1 Guardian Idol 1 Hammer of Nazahn 1 Haunted Cloak 1 Hedron Archive 1 Hedron Matrix 1 Helm of Kaldra 1 Infiltration Lens 1 Kaldra Compleat 1 Mind Stone 1 Nazgul Battle-Mace 1 Psychic Paper 1 Robe of the Archmagi 1 Rogue's Gloves 1 Shield of Kaldra 1 Sky Diamond 1 Sol Ring 1 Strata Scythe 1 Sword of Body and Mind 1 Sword of Feast and Famine 1 Sword of Fire and Ice 1 Sword of Forge and Frontier 1 Sword of Hearth and Home 1 Sword of Kaldra 1 Sword of Light and Shadow 1 Sword of Once and Future 1 Sword of Sinew and Steel 1 Sword of the Animist 1 Sword of Truth and Justice 1 Sword of War and Peace 1 Thought Vessel 1 Ur-Golem's Eye 1 Worn Powerstone Nope, instead we're going to do something completely different

It runs all of the expected cards with the common suite of four Karn Liberated and two each of the other top-end threats