Rofellos, Llanowar Emissary can't be a commander.

@mazrimtaim: True. I removed him from the list.

You may have missed Rafiq of the Many

NeoNexxa: Apparently I did. I added him. Thanks!

Nice list! I believe the color identity for Archangel Avacyn  ^Flip is Boros, not White, and that Avacyn, the Purifier  ^Flip can't be a commander, since she is the flip side of a playable card.

Also, you don't have to include any of these if you don't want to, but these are all the White commanders I could find that weren't in your list.

Atalya, Samite Master, Avacyn, Guardian Angel, Brigid, Hero of Kinsbaile, Brimaz, King of Oreskos, Celestial Kirin, Cho-Manno, Revolutionary, Commander Eesha, General Jarkeld, Gerrard Capashen, Guan Yu, Sainted Warrior, Hazduhr the Abbot, Hikari, Twilight Guardian, Hixus, Prison Warden, Huang Zhong, Shu General, Kataki, War's Wage, Kentaro, the Smiling Cat, Kiyomaro, First to Stand, Konda, Lord of Eiganjo, Lieutenant Kirtar, Lin Sivvi, Defiant Hero, Liu Bei, Lord of Shu, Major Teroh, Myojin of Cleansing Fire, Nagao, Bound by Honor, Opal-Eye, Konda's Yojimbo, Orim, Samite Healer, Oriss, Samite Guardian, Oyobi, Who Split the Heavens, Pang Tong, "Young Phoenix", Pianna, Nomad Captain, Radiant, Archangel, Rashida Scalebane, Rashka the Slayer, Rune-Tail, Kitsune Ascendant, Sensei Golden-Tail, Sidar Jabari, Soraya the Falconer, Takeno, Samurai General, Tivadar of Thorn, Yomiji, Who Bars the Way, Yosei, the Morning Star, Zhang Fei, Fierce Warrior, Zhao Zilong, Tiger General, and Zuberi, Golden Feather.

These are all the Blue commanders I could find that weren't in your list:

Aboshan, Cephalid Emperor, Alexi, Zephyr Mage, Alhammarret, High Arbiter, Ambassador Laquatus, Blind Seer, Braids, Conjurer Adept, Chisei, Heart of Oceans, Cloudhoof Kirin, Empress Galina, Hakim, Loreweaver, Heidar, Rimewind Master, Higure, the Still Wind, Hisoka, Minamo Sensei, Ixidor, Reality Sculptor, Keiga, the Tide Star, Lady Sun, Linessa, Zephyr Mage, Llawan, Cephalid Empress, Lu Meng, Wu General, Lu Su, Wu Advisor, Meloku the Clouded Mirror, Mistform Ultimus, Muzzio, Visionary Architect, Myojin of Seeing Winds, Patron of the Moon, Reveka, Wizard Savant, Soramaro, First to Dream, Sun Ce, Young Conquerer, Sun Quan, Lord of Wu, The Unspeakable, Uyo, Silent Prophet, Vendilion Clique, Venser, Shaper Savant, Zhou Yu, Chief Commander, and Zhuge Jin, Wu Strategist.

These are all the Black commanders I could find that weren't in your list:

Akuta, Born of Ash, Cabal Patriarch, Cao Cao, Lord of Wei, Cao Ren, Wei Commander, Commander Greven il-Vec, Crovax the Cursed, Gallowbraid, Grandmother Sengir, Greel, Mind Raker, Haakon, Stromgald Scourge, He Who Hungers, Horobi, Death's Wail, Hythonia the Cruel, Ihsan's Shade, Iname, Death Aspect, Infernal Kirin, Irini Sengir, King Macar, the Gold-Cursed, Korlash, Heir to Blackblade, Kuon, Ogre Ascendant, Kuro, Pitlord, Kyoki, Sanity's Eclipse, Lim-Dul the Necromancer, Maga, Traitor to Mortals, Maralen of the Mornsong, Morinfen, Myojin of Night's Reach, Ob Nixilis, Unshackled, Phage the Untouchable, Purraj of Urborg, Seizan, Perverter of Truth, Shauku, Endbringer, Sima Yi, Wei Field Marshal, Spirit of the Night, Toshiro Umezawa, Veldrane of Sengir, Visara the Dreadful, Volrath the Fallen, Xun Yu, Wei Advisor, Zhang He, Wei General, and Zhang Liao, Hero of Hefei.

These are all the Red commanders I could find that weren't in your list:

Adamaro, First to Desire, Balthor the Stout, Ben-Ben, Akki Hermit, Brothers Yamazaki, Chandler, Diaochan, Artful Beauty, Dong Zhou, the Tyrant, Fumiko the Lowblood, Hivis of the Scale, Homura, Human Ascendant, Iizuka the Ruthless, Ishi-Ishi, Akki Crackshot, Jeska, Warrior Adept, Jiwari, the Earth Aflame, Joven, Kamahl, Pit Fighter, Kazuul, Tyrant of the Cliffs, Kumano, Master Yamabushi, Kurkesh, Onakke Ancient, Latulla, Keldon Overseer, Lu Bu, Master-at-Arms, Ma Chao, Western Warrior, Mannichi, the Fevered Dream, Maraxus of Keld, Myojin of Infinite Rage, Rakka Mar, Rorix Bladewing, Ryusei, the Falling Star, Shimatsu the Bloodcloaked, Skyfire Kirin, Squee, Goblin Nabob, Starke of Rath, Tahngarth, Talruum Hero, Tarox Bladewing, Telim'Tor, Tuktuk the Explorer, Yuan Shao, the Indecisive, and Zurgo Bellstriker.

These are all the Green commanders I could find that weren't in your list:

Anthousa, Setessan Hero, Arashi, the Sky Asunder, Autumn Willow, Ayumi, the Last Visitor, Baru, Fist of Krosa, Bounteous Kirin, Eladamri, Lord of Leaves, Glissa Sunseeker, Hua Tuo, Honored Physician, Iname, Life Aspect, Isao, Enlightened Bushi, Iwamori of the Open Fist, Jedit Ojanen of Efrava, Jugan, the Rising Star, Kaysa, Kodama of the Center Tree, Kodama of the North Tree, Lady Zhurong, Warrior Queen, Masumaro, First to Live, Melira, Sylvok Outcast, Meng Huo, Barbarian King, Mirri, Cat Warrior, Myojin of Life's Web, Nemata, Grove Guardian, Polukranos, World Eater, Reki, the History of Kamigawa, Sachi, Daughter of Seshiro, Sakiko, Mother of Summer, Sasaya, Orochi Ascendant, Seton, Krosan Protector, Shisato, Whispering Hunter, Shizuko, Caller of Autumn, Silvos, Rogue Elemental, Sosuke, Son of Seshiro, Surrak, the Hunt Caller, Verdeloth the Ancient, Yisan, the Wanderer Bard, and Zuo Ci, the Mocking Sage.

These are all the Azorius commanders I could find that weren't in your list: Ayesha Tanaka, Gosta Dirk, Hunding Gjornersen, Ith, High Arcanist, Jedit Ojanen, Kasimir the Lone Wolf, and Tobias Andrion.

These are all the Dimir commanders I could find that weren't in your list: Circu, Dimir Lobotomist, Nebuchadnezzar, Princess Lucrezia, Ramirez DePietro, Riven Turnbull, Sivitri Scarzam, and Ur-Drago.

These are all the Rakdos commanders I could find that weren't in your list: Axelrod Gunnarson, Barktooth Warbeard, Lady Orca, Pavel Maliki, Rakdos the Defiler, and Rohgahh of Kher Keep.

These are all the Gruul commanders I could find that weren't in your list: Jerrard of the Closed Fist, Livonya Silone, Marhault Elsdragon, Stangg, Sunastian Falconer, and The Lady of the Mountain.

These are all the Selesnya commanders I could find that weren't in your list: Daughter of Autumn, Gabriel Angelfire, Jasmine Boreal, Kei Takahashi, Lady Caleria, Lord Magnus, Sir Shandlar of Eberyn, and Torsten Von Ursus.

These are all the Orzhov commanders I could find that weren't in your list: Selenia, Dark Angel.

These are all the Golgari commanders I could find that weren't in your list: Iname as One, Rhys the Exiled, and Thelon of Havenwood.

These are all the Boros commanders I could find that weren't in your list: Munda, Ambush Leader.

These are all the Grixis commanders I could find that weren't in your list: Mishra, Artificer Prodigy.

These are all the Jund commanders I could find that weren't in your list: Bartel Runeaxe.

These are all the Naya commanders I could find that weren't in your list: Jacques le Vert.

These are all the Five-Colored commanders I could find that weren't in your list: Atogatog.

Great resource. THanks!

@DaringApprentice: Thanks for the info. I'll have a look at them. (I might not add all of them as I don't want this list to be filled with crappy commanders.)

That's totally understandable. From experience, I've seen a Selenia, Dark Angel deck dominate an entire game.

Also, just as a heads up, Rhys the Exiled has a Golgari color identity, not a Green one, but you have him listed in both sections.

With Command Beacon, Phage the Untouchable and Haakon, Stromgald Scourge are totally viable

You can also counter Phage the Untouchable with any of Thrull Wizard, Withering Boon, Dash Hopes, Kozilek, the Great Distortion, Chalice of the Void, Nether Void, or a combo with Deathgrip and Painter's Servant, and then recover it from your graveyard to your hand, so I'd say Phage the Untouchable is playable.

...psst...@DaringApprentice...

Painter's Servant is not legal in EDH

Oh woops, my bad! Forgot to check that before I posted, thank you for the catch!

You are missing over 100 possible commanders. Clickbait..,

Did you read the description, Colgate? It says

"Note: I don't include all legendary creatures as commander. Some legendary creatures are really bad commanders and I don't want to fill this list with bad commanders. I don't want you to have to filter out all the really bad commanders yourself, so I did that for you. That being said, I may still have forgotten some great commanders or added some crappy ones."

I was referring to title "All Possible Commanders". Description can't be clickbait, because you don't see it until you click.

You have plenty of terrible commanders there: Sidar Jabari, Soramaro, First to Dream, Spirit of the Night, Skyfire Kirin, Shisato, Whispering Hunter, Geist of Saint Traft, Teysa, Envoy of Ghosts, Tajic, Blade of the Legion, Asmira, Holy Avenger, Skeleton Ship, Tor Wauki, Sisters of Stone Death, Stangg, Chromium, Treva, the Renewer, Oros, the Avenger, Daghatar the Adamant, Johan, Sol'kanar the Swamp King, Vorosh, the Hunter, Vaevictis Asmadi, Atogatog and more.
Also you are still missing at least one semi-strong commander from the list, Seton, Krosan Protector

imagine having Hope of Ghirapur as your commander

@skywatcher: On EDHREC, there're 172 decks with Hope of Ghirapur as their commander, so yes. There're some that imagined that. :)