When starting out playing Warhammer 40K, it can be overwhelming to face the vast number of armies on offer. From loyal soldiers of the Imperium, to the terrifying forces of Chaos, to the diverse ranks of the Xenos, there are many choice for the aspiring wargamer.

But which ones are the strongest? Which armies will let you destroy your enemies, defeat your friends, and take the champion slot? This list will run down the strengths and weaknesses of the 10 most powerful armie, guiding you which one to pick.

10. Genestealer Cults

Purple-skinned Purestrain Genestealers swarm over the Adeptus Mechanicus

The Genestealer Cults are fanatic alien monsters, born of genetic manipulation of normal human citizens by terrifying and cunning tyranids called Genestealers, and are experts at guerilla warfare in the grimy factories of the Imperium’s worlds.

The main draw of the Genestealer Cults is, as their name suggests, the large number of fanatic troops they have at their disposal. These low-cost troops allow you to send many large squads of core units into battle. Though these troops are weak, their powerful ‘Cult Ambush’ ability allows you to send in hidden squads to replace them when they fall. The reinforcing units can then blast through the enemy’s cover using the powerful ‘They Came From Below’ detachment ability. This allows you to control the entire battlefield and claim many objectives at once, even those behind enemy lines.

But hordes of infantry are not their only strength; the genestealer cults also have some powerful leaders, such as the psychic Magus, who can mind-control enemy units, and the hulking Abominant with his regenerating health and brutal Power sledgehammer, as well as backup from a few large industrial vehicles such as the Goliath Truck which can transport your troops in to battle while allowing them to fire out, and the Goliath Rockgrinder, which swaps half of its transport seats for a powerful flamethrower.

Genestealer Cults Strengths:

• Cheap but strong battleline units - Especially Neophyte Hybrids
• Strong battlefield control - Deep Striking, Ambushing and Counter attacking
• Flexibility in tactics - Strong toolkit of stratagems

Choose Genestealer Cults if…

• You enjoy the idea of leading gangs of aliens wielding industrial equipment as weapons and driving modified mining vehicles!
• You like to charge at your enemies with lots of units
• You’re willing to learn their long list of stratagems before you can reach their full potential

A Genestealer Cults army ambushes a patrol of Chaos Space Marines in an industrial forge

9. Thousand Sons

The sorcerer Ahriman leads his Thousand Sons into battle, flanked by waves of daemons.

The Thousand Sons are one of the chapters of the Chaos Space Marines, enhanced soldiers of the Imperium who were corrupted by chaos many centuries ago. They have a specific focus on dark magic, and as such are lead by powerful sorcerers.

With strong defensive capabilities and some powerful magic blasting, the Thousand Sons are a great army for holding back, letting the enemy come to you, and then destroying them at mid-range. This is especially supplemented by their army rule ‘Cabal of Sorcerers’ which allows you to use your psyker units to execute powerful magical spells called rituals. These have a variety of options, some damaging, but mostly executing dangerous debuffs on you enemies.

With your foes weakened, you can then send the slow moving Rubric Marines or the bird-face hordes of Tzaangors to attack, doing large amounts of damage, and keeping the enemy away from your objectives. You are also able to take daemons of Tzeentch in your army such as the Blue Horrors or Pink Horrors, who are both fire-breathing monstrosities who can add to your damage output and crowd control. Finally, you can lead your army with the enormous Magnus the Red, a lord of war unit who is incredibly powerful. His Blade of Magnus weapon and his stunning 14” movement speed, combined with a very diverse range of psychic powers, make him a force to be reckoned with on any battlefield.

Thousand Sons Strengths:

• Powerful magical abilities for shutting down enemy advances
• Strong Objective Defence: Slow but powerful units
• Lead by one of the strongest psychic units in the game

Choose Thousand Sons if…

• You enjoy the aesthetic of cursed, ancient sorcerers corrupted by daemonic influence
• You like to blast your enemies with small groups of powerful warriors
• You think the best offence is a good defence 

Magnus the Red leads the way, wings outstretched

8. Orks

Ork boyz blast through the battlefield in a wave of fire

The Orks are the meanest bunch around. If there’s a fight happening, they’ll be there, charging in to WAAAAAAGH!

Orks are an interesting choice, due to the versatility of options found in their army list. They’re not purely melee or ranged focused, and therefore aren’t best-in-class in either, but they have strong units in both categories, allowing a dangerous strategy - clearing the meat wall with gunfire from fast vehicles and ground troops, and allowing melee infantry to charge through and get to the enemy’s core units. Their army ability, ‘Waaagh!’ allows all units to both advance and charge, as well as giving buffs across the board, for a single turn, which can give them a brutal midgame.

Their core units, Boyz and Beast Snagga Boyz, both provide a powerful and versatile battleline, especially when lead by the Warboss or Nob with Waaagh! Banner, who both can buff the units they lead. The Beast Snagga Boyz are especially strong against vehicles and monsters, so they can be a fantastic choice when fighting more tank-heavy armies like Tyranids or Astra Militarum. These are accompanied by some truly awesome vehicles, especially the Blitza-bommer and the Rukkatrukk Squigbuggy. But the true jewel in their crown is the enormous Stompa, a massive weapons platform covered in cannons and chopping blades. This can rival even the likes of an Imperial Knight in a one-on-one battle, and will absolutely destroy anything lesser.

Orks Strengths

• Great list versatility - many options
• Very strong anti-tank capabilities
• Army ability can end the game in one fast strike

Choose Orks if…

• You’re interested in leading a horde of scrappy alien troopers who like nothing more than war
• You like to end your enemies with overwhelming force rather than relying on tactics or objectives
• You like building complex miniatures with many parts

The green tide overwhelms an imperial guard battalion, with the enormous Stompa in the background

7. Leagues of Votann

A mighty Kahl rallies his troops to take down a terrifying Hive Tyrant

The Leagues of Votann are a network of clans of humans, who evolved to be short and squat due to the high-gravity worlds they live and mine on. They will stand their ground against anything, writing a long list of grudges against their enemies which they never forget.

The Leagues’ primary strength is their strong output of firepower. They can blast their way through pretty much any threat, given that enough of their soldiers are in the right place at the right time. This makes their vehicle choices, mostly large troop transports, essential to their strategy. If they can get everything into place, they can use Judgement Tokens, given by their army rule ‘Eye of the Ancestors’, to rain down fire on anything in their path.

The key to pulling this off is a combination of the transport vehicles such as the Sagitaur and the Hekaton Land Fortress, as well as carefully placing core units such as the Hernkyn Pioneers and Hearthkyn Warriors in reserves and bringing them in later as reinforcements. This can make their early game a little weak,as it takes some time before all of your units are actually in the battle, but once everything is in the field, they can really hold their own. The main difficulty for the Votann lies in their short army list - they just don’t have enough unit options to really pull off complex strategies.

Leagues of Votann Strengths

• Very strong ranged attacks
• Simple army building - only a few options
• Powerful army rule with some complexity

Choose Leagues of Votann if…

• You would like to lead battalions of dwarf warriors with high-tech lasers and futuristic vehicles
• You like to get everything set up before you eviscerate your enemies
• You don’t want to spend too long choosing which units to include in your army

Two Hekaton Land Fortresses unload a wave of troops to charge down the Orks

6. Adepta Sororitas

A cannoness leads her troops while their temple-ship gather in the skies

The Adepta Sororitas, or Sisters of Battle, and an all-female army pledged to the Ecclesiarchy, the holy church of the Imperium. They cleanse worlds with sanctified flame, destroying heresy wherever it emerges.

The Sister of Battle are renowned as a very reliable army choice, leaving nothing up to luck.
Their army rule, ‘Acts of Faith’ gives them the best guaranteed success possible - that is, replacing dice results with pre-rolled miracle dice. This, combined with strong invulnerable saves across the board, makes them a very solid choice for many different tactics or styles of army build. While they mostly focus on ranged attacks, they have some brutally strong melee units which, if they can get into position fast enough, can smash through enemy lines and capture objectives with ease.

One of their main draws is the very solid list of units with few weak choices. This means you can manage a lot of different playstyles. You can focus on powerful leaders, such as the massive power-armour clad Mordenn Vahl or the healing-focused Saint Celestine; you can focus on cost-efficient ranged units such as the Battle Sisters Squad or Repentia Squad; or you can focus on fast hit-and-run units, such as the flying Seraphim and Zephyrim Squads or the Death Cult Assassins. The only thing that hold them back compared to other armies is their low wound count and lack of heavy support options or powerful vehicles- which means that if you aren’t careful, armies with a lot of long-ranged blasting capabilities may take your units out before they can get into position.

Adepta Sororitas Strengths

• Very powerful army ability
• Versatile army list options
• Powerful close-ranged units - once they’re in place

Choose Adepta Sororitas if…

• You want to lead warrior nuns into battle, slashing heretics left and right and cleansing the battle with sacred flame
• You like to have a lot of choices in terms of army setup
• You prefer small units of warriors over vehicles and monsters
• You aren’t interested in psychic powers - they don’t get any!

The Sister of Battle hold back chaos forces, defending a key objective

5. Chaos Space Marines

Chaos Space Marines attack a mountain fortress, lead by the hulking Hellbrute

The Chaos Space Marines are the enemy of all that is good, just and right in the galaxy. Once noble heroes of the Imperium, they were corrupted by chaos during the Great Heresy, and now fight to destroy the Imperium alongside daemonic allies.

In terms of playstyle here are a few different options for the Chaos Space Marines, each equally powerful. They can act as an elite army with only the most powerful space marine and vehicle units - they can gather Chaos Daemons as allies to act as fast skirmish units for taking objectives- or they can focus on cultists, taking key units and stratagems to buff the normally-weak units into powerful waves of regenerating foes. Each of these strategies can be rather powerful, when focused on exclusively - but trying to split roles can lead to disaster.

For the elite playstyle, the star of the show is Abaddon the Destroyed, warmaster of the chaos legions. With a whopping 9 wounds, and various powerful choices for buffing the units he leads, Abaddon is one of the best units in the game outside of Lord of War units. Chaos Terminators, with fantastic anti-tank capabilities, and Plasma Forgefiends, with anti-horde blasting, round out the elite list. For the skirmish focused list, the toxic Nurglings, who can charge in for cheap, sorcerous Blue Scribes, who can teleport your units into battle, and Flamers, who fly in at high speeds, are the main focus, generally supported by some basic Legionaries. The cultist list instead relies on the Dark Commune leader unit to give your cultists an invulnerable save, to keep them alive for longer, as well as Accursed Cultists, who can regenerate their forces every turn. All of these options keep your enemies guessing, while giving you as many choices as possible.

Chaos Space Marines Strengths:

• Strong elite characters
• Objective Sweeping
• Horde army options
• Strong damage output across the board

Choose Chaos Space Marines if…

• You want to lead the most corrupted, evil characters in the galaxy, accompanied by terrifying daemons and grimy cultists
• You like having a lot of versatility in your army list choices
• You prefer to focus on damage and positioning rather than complex strategy

Chaos Space Marines of the Night Lords muster in a ruined church

4. Black Templars

A Castellan of the Black Templars leads his forced to defend a hive-world of the imperium

The Black Templars are a chapter of the Space Marines, the supersoldier heroes of the Imperium. More so than any other chapter, the Templars are defenders of the Imperial Faith, venerating the Emperor as a literal God.

The Templars are unique among space marines in that their detachment rule forbids them from taking any psykers at all- similarly to with the Adepta Sororitas, they see psychic magic as heresy. They instead rely on powerful ‘Templar Vows’, which buff your units with a different bonus each round, rotating between physical defence, psychic defence, and increasing your already strong melee output, as the case may be depending on your needs. This, plus their unique variants of the standard space marine units, more than make up for their lack of psychic output and make them a force to be reckoned with.

The bread and butter of the Black Templars is their special units - the Crusader Squad, Primaris Crusader Squad, and Primaris Sword Brethren. These units have special high-powered melee options, especially the Sword Brethren, as well as decent ranged options to back them up. They also have special variants of many vehicle options from the normal space marines codex - The three variants of the Black Templars Gladiator tank are especially notable in their addition of Multimeltas- a weapon option not available to their cousins. Their Chapter Master, High Marshal Hellbrecht, is also a must-have, with an incredible 12 attacks per round using the mighty Sword of the High Marshals.

Black Templars Strengths:

• Enormous melee output
• Powerful vow buffing
• Very interesting and unique options

Choose Black Templars if… 

• You want to lead a noble crusade of some of the strongest and most brutal Space Marines there are
• You like to charge your enemies mercilessly, focusing on damage over all else
• You prefer not to worry about psychic options

Chainswords revved and ready to go, the Black Templars look to their High Marshal

3. Deathwatch

While the planet is blasted by the Xenos fleet, Deathwatch hold the line on the ground

Deathwatch are another group of Space Marines, but not strictly a chapter in their own right. instead, they collect the strongest marines of the other chapters to protect the Imperium against the alien forces who would see it destroyed.

This army is really the one to pick if your main focus is on damage and destruction. Their already-potent damage can be buffed using the Space Marines ‘Oath of Moment’ army rule in key moments to end anything in their path- but they don’t rely on it. Their ‘Mission Tactics’ Detachment Rule make every turn successful, allowing you to give out keywords to all your units’ weapons and keep dealing that high damage as much as possible. Their ‘Kill Teams’ army rule is also very interesting - this allows you to create composite units containing different types of marines, which can give you a lot of versatility

The main damage dealers of Deathwatch are the Deathwatch Veterans -especially in melee if you equip them with the unique Deathwatch Thunder Hammers-, the Proteus Killteam - who can be incredibly resilient when equipped with Terminators, and the absolutely broken Desolation Squad can be used in Deathwatch, pulled from the main Space Marines Codex. The Watch Master and Watch Captain Artemis both provide incredible support for your core units above, while the standard choices of Librarian, Apothecary Biologis, and Captain in Gravis Armour rounding out any list.

Deathwatch Strengths:

• One of the best damage outputs in the game
• Very flexible - buffs to match any lists’ specialties
• All the usual Space Marine options
• Very versatile killteam units

Choose Deathwatch if…

• You want to be the first line of defence against the hordes of xenos who threaten the Imperium, the best of each chapter
• You love to focus on destruction and death, with versatile units that can face any foe
• You aren’t fussed about claiming objectives or executing complex manoeuvres

The Corvus Blackstar jets swoop down over the advancing Deathwatch forces

2. Aeldari

An Aspect Warrior of the Aeldari slaughters mutated and corrupted cultists

The Aeldari, also known as the Eldar, are an ancient warrior culture in its death throes. They see themselves as above all else in the galaxy, and wish the preserve their culture at all cost.

Now. The Aeldari. Only recently have they pushed from the top spot, so powerful was their original index rules - and it all comes down to ‘Strands of Fate’, their army rule. Fate Dice, gained from this rule, are incredibly powerful, as you can use them to substitute already-rolled results in whenever you later roll. This means that you can prepare some 6’s, and then slot them in at the perfect tactical moment. This greatly reduces the factor that chance and variability play - making the Aeldari incredibly reliable. They are also incredibly fast, have incredibly strong shooting, and have access to some of the best stratagems in the game. Their only weakness is low wounds - with enough damage output, even they can be wiped out.

Their most powerful units lie in the characters section of the index: Most notable are the huge and devastating Avatar of Khaine, the Autarch providing extra command points for tactical versatility, and the Farseer with its immense psychic output. The powerful Phoenix Lords can also be incredibly strong when they lead their specific focused units. While the core units of the Aeldari are not the strongest (and are generally more points-costly than the are worth), the elite fighting forces more than make up for this- especially due to their incredible speed. Swooping Hawks, Warp Spiders, and Shadow Spectres, are all must-takes, and their battlefield control can be further improved by incredible stratagems, especially Feigned Retreat and Fire and Fade, which both allow the Aeldari extra movement while still keeping their shooting output high. Overall, this leads to an incredibly strong combo.

Aeldari Strengths:

• Best firepower
• Fastest units - lots of battlefield control and claiming objectives
• Reliable due to Strands of Fate

Choose Aeldari if…

• You want to lead noble warriors into battle, striking with speed and grace
• You like fast, skirmishing units, who can focus on claiming objectives, aswell as a focus on shooting
• You don’t mind annoying your friends with your ability to kill their units and escape before they can retaliate

The Avatar of Khaine raises his sword, surrounded by Aeldari warriors

1. Necrons

An army of Necrons, rising from the crypts of their tomb-world

The Necrons are an ancient people who ruled the galaxy millions of years ago, but gave up their physical forms, using advanced technology to transfer their consciousness’ into mechanical bodies, and then sealed themselves away. Now, they reawake, wanting to reclaim what they lost…

The Necrons didn’t begin 10th edition at the top of the pile, but their recent codex update has given them some of the best options on the table- especially the Canoptek Court detachment with its ‘Power Matrix’ ability, which gives you unparalleled battlefield control. This allows units in certain zones of the battlefield, determined by how many objectives you control, to re-roll all hit rolls - which hugely increases their chances to hit. This combines with their powerful stratagem options, which rely on the Power Matrix. If you can claim enough of the neutral objectives in the early game, this can create a devastating cascade, bringing the army to a swift win. Necrons units are fairly slow, but they make up for this with some of the most resilient units - both in terms of Toughness and Wounds. Their core army rule is also very strong - ‘Reanimation Protocols’ allows some already - tough units to return to the battlefield when destroyed.

Necrons really rely on their leaders to get by, with some very powerful buff. They usually have one character per unit, with the Plasmancer, Psychomancer, Chronomancer and Royal Warden being fantastic choices to lead the Battleline Immortals or Necron Warriors. The named characters such as The Silent King and Trazyn the Infinite are also incredibly powerful, providing multiple buff options to their commanded units. Those already strong battleline units can mitigate their fallings with these strong buffs. The Canoptek vehicles also shine - their huge number of wounds and brutal shooting, as well as supporting abilities for their surrounding allies, make them absolutely monstrous. Overall, the Necrons have an incredibly strong list, especially boosted by the new codex rules - but the upcoming balance dataslate may change those buffs.

Necrons Strengths:

• Toughest units in the game
• Very powerful new detachment abilities
• Incredible troops
• Very powerful stratagems

Choose Necrons if…

• You want to lead a slow, creeping, unending tide of ancient warriors, filled with mystery
• You want to dominate the battlefield, blasting everything in your way and taking everything your enemy sends at you in your stride
• You prefer a few big, bulky and complex units over a horde of small omes

The C’tan Shard of the Nightbringer approaches, sweeping through the Necron lines.

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