Part of playing any format is to know about and understanding the most powerful decks. While there's a case for "mono-blue-stealstuff" and "ooze-combo" to be declared the most powerful, my belief is it's the most broken commanders that enable the most broken decks.

I held a brief, unscientific twitter poll the other day to get a quick consensus on what the most broken commanders are. Here are the results.

(Click to see it full sized!)

They roughly align with my understanding of the metagame. There's a case to be made that Glissa, The Traitor belongs on the list, but the current build is really a finely tuned Necrotic Ooze/Hermit Druid-combo deck that could easily be seen in Teneb, The Harvester or any other G/B/u/r/w build. The same for Vendilion Clique, who provides an unprecedented level of hand disruption, but otherwise are basically a mono-blue-control deck.

Here are the current six most broken archetypes in Commander. Note that they all include one particular color (#BanIslands).

Zur, The Enchanter

Zur is widely acknowledged as the most-broken of commanders. He provides constant, consistent tutoring on a unprecedented level compared to other commanders. This allows him to be a true "build around me" toolbox commander, able to grab such enchantment greatest hits as Necropotence, Stasis, Standstill, Land Tax, and Oblivion Ring, all with the ability to recur these through Replenish and Retether. The deck back ups this up with a strong counter-magic package and a light land-destruction package; with Zur on the table and protected you simply don't need mana any more. The deck also runs Winds of Rath, a context-sensitive Wrath of God that only Zur (or Uril, The Miststalker) could love.

The deck aims to protect Zur through several key cards, of which Diplomatic Immunity is the most important. Unfortunately (or fortunately?) the card isn't available on Magic Online yet, so the back up plan of either Vanishing or Flickerform is required. The order of tutor targets usually is as follows:

Stage 1: Diplomatic Immunity & Vanishing/Flickerform to avoid spot removal and mass removal.

Stage 2: Necropotence & Solitary Confinement to get the card-advantage machine going and prevent opponents from killing you.

Stage 3: Daybreak Coronet & Empyrial Armour/Steel of the Godhead to kill your opponents, fast.

The deck also has a couple of 'standard' packages built in.

• An Isochron Scepter package that may include Orim's Chant, removal, tutors, counterspells, etc.
• A Trinket Mage package including mana fixing, graveyard removal, library manipulation and creature removal.

There are only two real weakness of the Zur:

• The 3-colour casting cost of Zur makes landing a T1/2 Zur nigh impossible. As such the early game is really a game of protect and counter while the mana ramping and fixing occurs.
• Making it to that first attack step. Zur won't trigger if he doesn't get to attack, which is why he's often played with either Greaves on the table or counter-magic in hand. But once he's down and active, his opponents do not have a lot of chance to win.

Here's a decklist. The Luminarch Ascension is a nod to multiplayer play, not that the deck really needs it.

Azami, Lady of Scrolls

Azami, Lady of Scrolls aims to bury opponents in overwhelming card advantage with a side dish of infinite mana. Essentially a Wizard tribal deck, the deck achieves its ends through a number of blue-based combos, including Azami + Mind Over Matter to cycle (for free) through the entire deck to find the exact card needed at the right time. The deck isn't necessarily the fastest in the world, but it certainly has the best long game plan, making it brilliant for multiplayer games. It's just fine 1 on 1 as well, if it has a hand of early disruption and countermagic. The deck plays as follows:

Stage 1: Counter everything while trying to maintain hand size, if possible.
Stage 2: Play out Azami and a couple of other mages under counterspell protection to maintain card advantage and find an infinite mana combo.
Stage 3: Play out the combo, [card Stroke of Genius]Stroke[/card] out opponents or take infinite turns (whatever the build).

The deck includes the following packages:

• An infinite mana package including High Tide/Crystal Shard & Palinchron and Power Artifact & Grim Monolith, usually used to 'Stroke' opponents out of the game.
• A tribal Wizard package usually including Sigil Tracer, Patron Wizard, Willbender, Apprentice Wizard, Voidmage Prodigy, Venser, Shaper Savant and Trinket Mage, all of which get protection from Riptide Laboratory.

Azami doesn't have a lot of weakness, largely due to the resilience of the card advantage. However you can push through by:

• Using fast aggro to bash your way through the early countermagic and put your opponent on an undeniable clock. Infect decks are extremely useful in this fashion.
• Using prison style decks to keep Azami off mana - infinite or otherwise - and deny other resources to prevent the deck from achieving mass card advantage.

Here's a deck list.

Arcum Dagsson

The most powerful Arcum Dagsson decks are prison decks with a strong denial theme. The key to these types of deck is Winter Orb backed by fast mana effects. Arcum Dagsson makes this possible through his constant tutoring effect, much like Zur, making him a consistent, reliable way of putting together the necessary prison pieces. The deck also likes to abuse Crucible of Worlds to keep opponents off lands while accelerating. The ability to run a Stax shell by abusing Master Transmuter is also a reliable win condition. The decklist plays out as follows:

Stage 1: Drop an artifact creature and Arcum as quickly as possible then tutor up Winter Orb + Icy Manipulator.

Stage 2: Hold the fort with countermagic while destroying opponents' resources with Smokestack/Strip Mine.

Stage 3: Tutor up win condition such as Memnarch or Tezzeret the Seeker and win game.

The deck has the following packages:

• A Master Transmuter package: For heavy abuse with Smokestack, Tangle Wire, Sundering Titan, and Blightsteel Colossus. By flashing Smokestack and Tanglewire in and hour with Transmuter the effects become one sided and pretty horrible for any opponent to compete against. The deck gets extra utility by abusing Copper Gnomes as well.
• A healthy recursion engine through Scarecrone + Academy Ruins for a constant stream of tutor targets and card advantage.

The deck has the following weaknesses:

• Humility: This deck relies on it's creatures (Dagsson, Master Transmuter, Copper Gnomes) to get going and has a hard time dealing with enchantments once they hit the field. Combine with Night of Souls Betrayal for extra punishment.
• Dedicated graveyard hate: The deck loves to abuse the graveyard so anything you can do to disrupt that slows the endgame down. Especially useful with dedicated artifact hate as well, such as Shattering Spree, Ancient Grudge and Krosan Grip - cards with flashback, storm, or replicate are a must against this deck as it can't counter them all.

Here's a decklist.

Jhoira of the Ghitu

Jhoira of the Ghitu is a bit of a glass cannon. Her power comes in casting massive spells for the low, low price of 2 mana. Jhoira wants to go off very quickly and protect herself from there, but often has no long-term game if Plan A fails. I find that if she hasn't put herself in an unbeatable position by Turn 4 or 5 she's often going to lose. Essentially, the deck tries to suspend the biggest, meanest thing it can quickly - an Eldrazi or a Colossus, for example - and then protect it's position through countermagic (surprise surprise). As a result she's far better in 1v1 play than multiplayer. The deck plays out as follows:

Stage 1: Drop Jhoira, then suspend (generally) two threats (preferrably an Obliterate effect and an Eldrazi).

Stage 2: Protect the threats until they land with countermagic and mass permanent destruction, letting Jhoira die in the process if need be.

Stage 3: Smash with threats once they come out of suspension.

The deck runs the following packages:

• Due to the desire to run through multiple upkeeps the deck runs a large amount of extra-turn effects, including Time Warp, Capture of Jingzhou, Temporal Manipulation and Walk the Aeons. Time Walk effects always break the game and Jhoira uses these to maximum potential.
• A land destruction package including Obliterate, Omen of Fire and Sunder to make sure when the end-game threats land there's no way for opponents to fight back against them.

The deck has the following weaknesses:

• Hinder: If you can Hinder Jhoira the deck is essentially dead, filled with over-costed cards and few ways to power them out. Naturally the Jhoira player will attempt to play around Hinder as much as possible and protect against it with countermagic of their own, so it's not a perfect plan.
• Riftsweeper & Pull From Eternity: There's nothing more hilarious than binning an opponent's threat before it ever has a chance to land and these two do the job nicely. Riftsweeper should make anyone's competitive Green deck for the utility against Swords to Plowshares alone, but does the job of hosing Jhoira nicely.

Here's a decklist (probably not the best Jhoira list that exists, but you get the idea).

Sharuum the Hegemon

Sharuum the Hegemon is both an excellent graveyard recursion engine and part of its own, personal, combo. Esssentially, if you have Sharuum in play and cast Sculpting Steel, or have Sculpting Steel in the 'yard and cast Sharuum, you can set up an infinite recursion loop. The only question is what you want to do with this: with Disciple of the Vault you can drain your opponents, with Intruder Alarm you can infinitely untap your creatures, and with Soul Warden you can gain infinite life.

Like Zur, Sharuum gains a lot from having access most of the best tutors in the format, including Enlightened Tutor, Vampiric Tutor, and Mystical Teachings. This allows the deck to maintain a level of consistency from both the library and the graveyard that other decks find hard to keep up with. However, unlike most of the other decks in the list, it can play a long game with varied approaches: a control game with counterspells and Memnarch, a Prison game with Winter Orb and Icy Manipulator, or a beatdown game with Magister Sphinx and Lightning Greaves ("35 to to you, go!").

The deck plays out as follows:

Stage 1: Mana ramp, play mass/spot removal and draw cards to control the board.

Stage 2: Tutor for key pieces of whatever machine is being assembled, be it prison (Winter Orb), beatdown, disruption (Sundering Titan), etc.

Stage 3: Use said machine to crush while, you guessed it, backing it up with countermagic.

The deck has the following packages, many of which are also in previously described decks:

• A Trinket Mage/Treasure Mage package along with the other tutors, allowing it to find what it needs whenever it needs to, whether it be land, removal, or bombs
• A graveyard abuse package, somtimes including Scarecrone, Sharuum, Argothian Restoration, Academy Ruins, Volrath's Stronghold, and more to get the maximum bang-for-buck from it's various enter-the-battlefield abilities
• A Master Transmuter package, often including Sundering Titan, Magister Sphinx, Sphinx Summoner, living weapons, Contagion Engine, etc.
• A Winter Orb package (Winter Orb, Voltaic Key, Icy Manipulator) in order to help slow down opponents.
• Occasionally a Stoneforge Mystic package to match the Trinket/Treasure Mage package that includes Umezama's Jitte, various Swords of Such and Such, and Lightning Greaves, generally because its action is in the red zone and this helps push the damage through, plus if an equipment is destroyed it can easily be recovered.

As a result of these the deck is highly resilient but doesn't 'combo out' in the same way as the other broken decks. Rather its power lies in its ability to adapt to the varying circumstances of any game - especially multiplayer games - and find the necessary pieces to find the win.

The deck has the following weaknesses:

• Dedicated graveyard hate: A great recursion engine is quickly undone by some dedicated graveyard hate, but the deck has so much you really have to put it to work. Land destruction for both Academy Ruins and Volrath's Stronghold, removal for the Crucible of Worlds to bring them back, and Hinder for Sharuum, plus removal for Scarecrone... you get the picture. Dedicated and knowledgably targeted.
• Color denial: It's not much but it's something. As the deck really requires all three colours to get going, taking down one of them can put the deck way back.

Here's a decklist.

Erayo, Soratami Ascendant

A well built Erayo, Soratami Ascendant deck is a sight to behold, capable of going off on T2 consistently. The deck is designed to flip Erayo as quickly as possible, then defend that position until a suitable win condition is found. The deck achieves this by running an large amount of 0 and 1 mana casting cost cards, backed up by a number of casting-cost reducers and mana rampers. This allows the deck to cast and flip Erayo very early on, making a catch-up by opponents nigh on impossible. The deck runs as follows:

Stage 1: Play out hand and flip Erayo to make board progression extremely difficult for opponents

Stage 2: Soft lock with Arcane Laboratory and restock hand to protect position with counterspells and lock opponents out of the game if possible.

Stage 3: Hard-lock with Teferi, Mage of Zhalfir/Knowledge Pool, Planar Portal/Beacon of Tomorrows and kill opponents using infinite mana/Blue Sun's Zenith.

The decklist below has a the following 'standard' package:

• A fast mana package of including legal moxes, Etherium Sculptor, Sapphire Medallion, and other fast mana artifacts in order to help speed up the flip.
• A Trinket Mage package essentially to find a zero-cost artifact to help flip Erayo.
• A Winter Orb package (Winter Orb, Voltaic Key, Icy Manipulator) in order to help slow down opponents.

The weaknesses of Erayo are:

• Disrupting the Erayo flip: Erayo flips only on the fourth spell cast on a turn, therefore the timing of playing Erayo becomes critical. Ideally you play Erayo on the turn you want to flip it. However if you play it too early you open yourself up to removal. Too late and your opponent can put two spells on the stack and Erayo won't flip at all. Therefore the best way to combat Erayo is to either sandbag instant removal or other instant spells to either get her off the table or prevent the flip from happening by upping the storm count past four when she's on the stack.
• 'Cannot be countered' Spells & Effects: Vexing Shusher and Boseiju, Who Shelter's All are the best way to push through Erayo as she effectively does nothing with these two on the board. Aether Vial can also work, but it's a little slow.
• Spending an extra spell to push through an enchantment removal spell (and hoping for no counter magic). If you're willing to let the first spell fail (and possibly be hoovered up by Guile), it's an option.

Here's a decklist. The Grand Architect is something I've been trying. This deck has the Teferi/Knowledge Pool win-condition, though Planar Portal/Beacon of Tomorrows or any other end-game lock will do.

So there you go, the six top archetypes in Commander, a competitive metagame defined. With any commander decklist there's infinite improvements, tweaks and changes to be made, so take them as a starting point (especially the mana bases, as they are based on what I own on Magic Online and not what's most competitive). I don't recommend you should play any of these outside of competitive play, but you should at least be aware of them if you see them on the casual tables.