* Arcane Orb's constant pure damage output is devastating to Dragon Knight.
* Dragon Knight's relatively low mana pool leads to heavy damage from Sanity's Eclipse, which also bypasses his armor.

* Arcane Orb's pure damage ignores Mars' Bulwark.
* Astral Imprisonment can be used to stop Mars from being disruptive or save allies from his abilities.
* Sanity's Eclipse deals high damage to Mars, due to his low intelligence pool.

* In the early game, a Dragon Knight without Black King Bar is basically defenseless against Viper.
* Viper can harass Dragon Knight at any time with his Poison Attack and Nethertoxin.
* Corrosive Skin reduces damage from Dragon Fire and inflicts damage to him.
* Viper Strike disables Dragon Blood, negating his main survivability.
* Viper Strike and Poison Attack can severely slow him down even with his Elder Dragon Form.
Additional:
* Dragon Knight is easily harassed by Poison Attack after the laning stage ends.
* Corrosive Skin protects Viper from Breathe Fire and returns damage.
* Viper Strike can disable Dragon Blood, Dragon's Knight main source of armor and health regeneration.
* Between Poison Attack and Viper Strike, Viper can keep Dragon Knight permanently slowed even in Elder Dragon Form.

* Nethertoxin breaks the damage block from Bulwark.
* Poison Attack and Viper Strike's slows make it difficult for Mars to contribute to fights due to his low mobility.
Additional:
* Viper Strike can disable Bulwark entirely, making Mars far less tanky. Using Nethertoxin inside Arena of Blood may discourage enemies from following up with Mars's initiation.
* Rod of Atos is currently common on Viper and keeps Mars in position long enough to be killed.
* However, Viper is not very tanky earlier in the game, so positioning against Mars is important for Viper since a well-timed Spear of Mars can be the end of Viper.

* Fury swipes can tear Dragon knight down as it stacks infinitely.

* Ursa is a special mention because despite Bulwark diminishing most of the damage Ursa does, he is quite durable, especially with Enrage, discouraging the aggressive all-in playstyle of Mars; Ursa can simply not target Mars.

* Timbersaw's pure damage will kill Dragon Knight surprisingly fast, especially if he gets caught in a bad position while laning.

* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, Dark Willow, Enigma, Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.

* Huskar can burn down Dragon Knight's health quickly during the early to mid game, but is not as effective during the late game. However, Life Break remains a constant threat due to the slow and percentage-based damage.

Additional:
* Huskar can negate Dragon Knight's passive with multiple trades of Burning Spear.

* Burning Spear's magical damage is very troublesome for Mars in the laning stage.
* Life Break's percentage-based magical damage bypasses Bulwark, and can also be used to jump in or out of Arena Of Blood.

* Heroes who rely on burst physical damage are affected by Lucky Shot's disarm: Terrorblade, Sven, Clinkz, Windranger, Alchemist, Dragon Knight, Legion Commander

* Swashbuckle is an auto attack and therefore ignores Mars' Bulwark.
* Shield Crash upgraded with Aghanim is an auto attack and therefore ignores Mars' Bulwark.
* Rolling Thunder makes him immune to magic, making Pangolier able to roll in and out of Mars' Arena Of Blood.

* In general, heroes that can slow down Dragon Knight's movement speed will do well against him. This includes Venomancer and others in addition to the heroes mentioned above.

* Venomancer's spells all deal magical damage, ignoring Bulwark.
* Venomancer's multiple slows are especially effective at kiting Mars.
* Plague Ward can attack through Arena Of Blood.
Additional:
* Venomancer's poison attacks are all magical damage, ignoring Bulwark.
* Venomancer's multiple slows are especially effective against Mars' low mobility.
* Plague Wards can attack through Arena of Blood.

* Heartstopper Aura and Reaper's Scythe go right through Dragon Knight's armor.

* Necrophos' largely magical damage completely ignores Bulwark.
* Ghost Shroud protects Necrophos from God's Rebuke but more importantly stops Mars from being a threat in lane.

* Heroes who rely strongly on melee physical damage will fare badly against Omniknight's Guardian Angel: Phantom Assassin, Juggernaut, Dragon Knight, Lycan, Ursa, Troll Warlord

* Heroes that can save their allies can be a big problem for Mars: Dazzle, Omniknight.

* Heroes that lose a great amount of their tankiness and become easier to finish off: Bristleback, Spectre, Phantom Assassin, Enchantress, Dragon Knight.
* Once you have an Aghanim's Scepter, Shadow Demon instantly reaches a new power spike and becomes a counter for a variety of heroes that have strong passives.
* Heroes that lose a great amount of their tankiness and become easier to finish off: Bristleback, Spectre, Phantom Assassin, Enchantress, Dragon Knight.
* Heroes that lose a great amount of damage output and become less threatening: Phantom Assassin, Sven, Slark, Phantom Lancer.
* You can always stack camps and farm the scepter with Shadow Poison.

* Heroes with break abilities: Shadow Demon (with Aghanim's Scepter), Viper.

* Heroes with long cooldowns on their abilities or ultimate will struggle against the relentless pressure provided by Fiend's Gate: Terrorblade, Dragon Knight, Omniknight.

* Firestorm and Pit of Malice are very disruptive in team fights, completely matching Mars especially since it can all be cast inside Arena Of Blood and also does percentage-based magical damage, negating Bulwark.
* Dark Rift can save any allies of Underlord trapped in Arena Of Blood.
* Atrophy Aura allows Underlord to lane against Mars quite well since he does not have the best base damage during the early game.
* Underlord is a common carrier of both Pipe of Insight and Mekansm/Guardian Greaves, allowing his team to combat Mars in the mid to late game.

* Berserker's Call forces Mars to face in the direction choosen.
* Counter Helix deals pure damage and can go through Bulwark.

* Decay, Soul Rip and Flesh Golem all deal magical damage which ignores Bulwark.
* Decay reduces Mars' natural strength and therefore his health pool, which is what he relies on to trade effectively in lane.

* Dragon Slave deals reliable magic damage during the laning phase against Mars.
* Lina's Eul's Scepter of Divinity and Light Strike Array combo can interrupt Mars from being disruptive for a decent amount of time and leave him vulnerable for follow up stuns.
* Laguna Blade deals massive magical damage, and pure damage with Aghanim's Scepter.

* It is difficult for Mars to trade blows with Ogre Magi in the early game thanks to his high base health, resistance and Ignite.
* Bloodlust can assist Ogre Magi or an ally in repositioning against Mars for its move speed bonus.
* Fireblast can interrupt and mitigate Mars from performing his skill combos, especially in combination with Multicast.

* Static Link saps Dragon Knight of his already low base damage, making him even more useless in a fight if he gets kited.
* Storm Surge makes Razor much faster than Dragon Knight, and hard to catch.
* Eye of the Storm melts Dragon Knight's armor and bypasses Black King Bar, his core item.

* Solar Guardian can save allies caught inside Arena of Blood.

* Nether Blast, Decrepify and Life Drain deal high magical damage and bypasses Bulwark.
* Nether Ward reduces the amount of abilities Mars can use during fights and forces Mars to be careful about the heavy mana cost of Arena Of Blood.
* Pugna is one of few heroes that can contest Mars' ability to push and defend towers early on.

* Time Dilation while Spear of Mars and God's Rebuke are on cooldown will make these abilities unusable for a long time, rendering Mars nearly useless.
* Mars cannot turn inside the Chronosphere, which makes it easy to attack him from the back, bypassing Bulwark completely.
Additional:
* Time Walk allows Faceless Void to escape or enter Arena Of Blood, and helps him recover from Mars' burst damage.
* Time Lock's magical damage ignores Bulwark.
* Chronosphere allows Faceless Void to reposition behind Mars, ignoring his Bulwark while he is helplessly frozen in time.

* Ball Lightning makes it almost impossible to catch Storm Spirit without someone else initiating for you.
* Overload is not reduced by Bulwark and the magical damage spam can wear down Mars quickly.
Additional:
* Storm Spirit's abilities all do magical damage, which can bypass Bulwark.
* Ball Lightning can escape through Arena of Blood and it is easy to dodge Spear of Mars.

* Mars' own father is a formidable foe because Zeus deals massive amounts of magical damage. The high damage, low cooldown nukes of Arc Lightning and Lightning Bolt combined with the percent health magic damage of Static Field will shred Mars' health because it bypasses Bulwark completely.

* Viscous Nasal Goo slows down Dragon Knight and lowers armor, locking him down and making him more vulnerable.

* Sticky Napalm slows turn rate, making it difficult for Mars to face frontwards, where Spear of Mars and Bulwark are effective. In combination with Firefly, which deals magic damage, Batrider can make quick work of Mars.
* Flaming Lasso disables Mars while enemies re-position themselves behind Mars to avoid Bulwark.

* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, Dark Willow, Enigma, Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.

* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, Dark Willow, Enigma, Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.

* Elder Titan's Natural Order completely nullifies Dragon Knight's high armor.

* Nukers who have set amounts of damage will really struggle against Lone Druid especially in True Form: Puck, Void Spirit, Mars.

* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, Dark Willow, Enigma, Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.

* Heroes with no mobility will take some good damage from Sand King's spells: Dragon Knight, Jakiro, Pugna, Earthshaker.

* Heroes that depend on disrupting fights with ability combos or big ultimate abilities are vulnerable to the long stun of Fiend's Grip: Disruptor, Death Prophet, Enigma, Faceless Void, Invoker, Lich, Magnus, Mars, Medusa, Outworld Destroyer, Phoenix, Puck, Queen of Pain, Shadow Fiend, Treant Protector, Underlord, Winter Wyvern, Witch Doctor, Zeus.

* Kunkka's Ghostship and Torrent disrupt fights in Arena Of Blood.

* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, Dark Willow, Enigma, Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.

* Because Exorcism's damage is not reduce by damage block abilities or items, Death Prophet can be very good against heroes who rely on armor to survive: Axe, Terrorblade, Morphling, Dragon Knight

* Heroes that withstand damage like Timbersaw, Bristleback, Dragon Knight and others will have their durability largely reduced when hit by an Ice Blast due to the risk of shattering.

Additional:
* Cold Feet and Ice Vortex both hinder Dragon Knight's movement greatly during teamfights.
* Ice Blast ignores Dragon Knight's armor, disables his health regeneration, and kills him prematurely.

* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, Dark Willow, Enigma, Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.

* Heroes with high health especially Strength heroes will take more damage on Sun Ray: Axe, Pudge, Bristleback, Mars.

* Shadow Fiend's Presence of the Dark Lord reduces Dragon Knight's armor considerably, and his strong base attacks are augmented by his Necromastery.

* Shadowraze deals magic damage and ignores Bulwark.
* Requiem of Souls deals magic damage and can fear Mars away, forcing him to turn around and therefore become vulnerable.

* Slardar can chase Dragon Knight down with Guardian Sprint and stun him with both Slithereen Crush and his passive Bash of the Deep. He can also use Corrosive Haze to whittle Dragon Knight's armor.

* Heroes that can save their allies can be a big problem for Mars: Dazzle, Omniknight.

* Heroes that relies on armor or other type of physical damage negation are easy for Gyrocopter to take down during the early game with his magical damage: Axe, Dragon Knight, Sven.

* Heroes with high magical or pure damage will bypass Bulwark: Timbersaw, Dark Willow, Enigma, Invoker, Pugna, Skywrath Mage, Tinker, Zeus, Oracle.

* Rage, acting as a pseudo-Black King Bar, completely negates Mars' initiation if used in time.
* Feast does damage and heals based on max health, perfect against high-health strength heroes like Mars.
* Infest allows Lifestealer to potentially save allies from Mars' initiation with a quick burst of extra health.

* Lich's constant slows with Frost Blast and Chain Frost will slow Dragon Knight to a crawl, especially in a crowded teamfight.

* Rebound allows her to jump in or out of the Arena Of Blood. She can save her allies from the Arena with Dispose as well.

* Counterspell can helpful blocked off to Dragon Tail.
Additional:
* Counterspell makes Anti-Mage exceptionally resistant to Breathe Fire, Dragon Tail, Fireball (requires Aghanim's Shard) and Elder Dragon Form's attacks. Its active component also blocks and reflects Dragon Tail back at Dragon Knight.
* Mana Break drains Dragon Knight's small mana pool, although it won't affect Dragon Knight much if he is in his Elder Dragon Form.

* Snowball can protect Tusk and his teammates from a Spear of Mars' stun after an Arena of Blood, and with proper targeting, even bring them out of the Arena. This is especially noticeable in the earlier stages of the game before allies buy Black King Bar and rely on this less. Even during the late-game, Tusk can purchase a Blink Dagger to save allies that are caught before Black King Bars can be used by Blinking in and Snowballing out.
* Tag Team is a constant threat to Mars in-lane, as it deals significant damage and slow, making Bulwark slightly ineffective.
* It is worth noting that Ice Shards can be detrimental to Tusk's own team by creating terrain that Spear of Mars can latch on, though using it conservatively is a good enough solution in most cases.

* Blink Strike gives bonus backstab damage and can bypass Bulwark. Defensively, it could be used to teleport away from Mars, especially while inside Arena of Blood.
* Smoke Screen can interrupt Mars' skill combos, especially when cast inside Arena of Blood.
* Tricks of the Trade can be used to evade Mars' skills, which have a slight delay to them. It could also be used to buy himself time while trapped inside of Arena of Blood.
Additional:
* Bulwark is generally irrelevant against Riki as he primarily deals bonus damage from behind.

* Legion Commander is both good and bad vs Mars, on the plus side she can dispel Spear of Mars with Press the Attack and is a good Silver Edge carrier. However, Mars is not an ideal Duel target, as Bulwark will force her to 1: Buy Silver Edge, and 2: Hit Mars with it before the Duel, allowing a skilled Mars to react, especially with Eul's Scepter of Divinity. In teamfights, Mars will happily draw attention after using his abilities, and tank the Duel with all spells on cooldown.

* Medusa's Stone Gaze forces Mars to choose between getting petrified, or turning his vulnerable back on Medusa.

* Durable heroes relied a lot on their main passive effects and items' effects such as Bristleback, Underlord, Spectre and Dragon Knight can be disabled easily with Sharpshooter's break, reducing their potential in teamfights.

* Dragon Knight has no built-in disengage from Frost Arrows, and Marksmanship procs ignore base armor, bypassing Dragon Knight’s durability for the most part, making Drow one of the few heroes that can deal enough sustained damage to solo kill Dragon Knight.
* With Aghanim's Scepter, Frost Arrows also apply hypothermia stacks, reducing her target’s regen, which is especially potent against tanks like Dragon Knight. (A similar effect can also be achieved with an Eye of Skadi).