* 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.

* Sanity's Eclipse does massive damage to Wraith King who naturally has a low mana pool and typically doesn't build items to increase it.
* Wraithfire Blast's slow projectile speed makes it easy to avoid using Astral Imprisonment.

* 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.

* In general, attacks of the melee heroes who are entirely reliant on dealing physical damage and/or have very little to no area-of-effect abilities will make Underlord tickle and will have no effect against him, and will be unable to ambush Underlord and his team if Underlord chooses to use Dark Rift to get to a designated point of the map: Phantom Assassin, Terrorblade, Troll Warlord, Drow Ranger, Phantom Lancer, Chaos Knight, Sven, Wraith King, Bounty Hunter, Alchemist, Templar Assassin, Nyx Assassin, Bane.

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

* Invoker can drain Wraith King's mana with EMP, preventing him from reincarnating unless Wraith King has his Aghanim's Shard.
* Even if Wraith King survives and reincarnates, Invoker still has an arsenal of spells to lockdown Wraith King, including an easily setup Ice Wall.
* Tornado applies an area dispel to clear skeletons.
Additional:
* EMP allows Invoker to burn Wraith King's mana to prevent Reincarnation from triggering (only until Wraith King gets his Aghanim's Shard).
* Ice Wall and Cold Snap are particularly crippling for Wraith King as they allow to kite him very effectively, preventing him from dealing melee attack damage.

* Heroes who are reliant on physical damage will be nullified by Decrepify: Riki, Wraith King, Juggernaut.

* 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.

* Bulwark is generally irrelevant against Riki as he primarily deals bonus damage from behind.
Additional:
* Blink Strike gives bonus backstab damage. Along with Tricks of the Trade it completely bypasses Bulwark.

* Riki is a natural Diffusal Blade carrier, and it doesn't help that he's easily capable of sneaking up on Wraith King due to Cloak and Dagger.
* Riki can use Smoke Screen on top of Wraith King as he is reincarnating, making him a sitting duck for his second life. In addition, the blind prevents Wraith King from landing critical hits from Mortal Strike.
* Wraithfire Blast is quite predictable, and if Riki can react fast, he will disjoint it with Tricks of the Trade. There is also a chance he will become invisible again as the projectile travels, disjointing it.

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

* Heroes who rely on basic attacks will suffer from Laser: Phantom Assassin, Wraith King, Huskar.

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

* Heroes with area dispel can kill multiple skeletons at once: Brewmaster, Oracle.

* Wraith King, Medusa, Storm Spirit and other mana dependent heroes will have diminished impact on a fight if they survive Fiend's Grip due to its mana steal.

* 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.

* 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.

* 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.

* 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.

* Solar Guardian can save allies caught inside Arena of Blood

* 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.

* 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.

* Wraith King's lack of area of effect spells makes him easily overwhelmed by Beastmaster's summons.

* 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.

* If Mars lanes middle, Shadow Fiend can keep the lane pushed against him.
* Shadow Fiend can go an entirely magical based build, which is very effective against Mars.

* Berserker's Call forces Mars to face in the direction choosen.
* Counter Helix is a much stronger lane trader than Spear of Mars.

* 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 from Mars' Arena Of Blood.

* Mars has no way to trade with Ogre Magi in the early game thanks to his high base health, resistance and Ignite.
* Once Ogre Magi gets level 2 he may also have Bloodlust, which makes him even harder to deal with in lane.
* Fireblast can be ridiculously strong later on in the game for controlling Mars.
* Spear of Mars, which is Mars' main source of damage in the early game, cannot guarantee kills early on Ogre Magi.

* Wraith King has no form of AoE to clear Chaos Knight's illusions from Phantasm.
* Wraith King is very vulnerable if he reincarnates in the middle of his illusions.

* 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.

* 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.
Additional:
* 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.

* Sticky Napalm slows turn rate, making it difficult for Mars to control the direction he is facing to activate Bulwark.
* Flaming Lasso disables Mars while enemies re-position themselves behind Mars to avoid Bulwark.

* Wraith King has a very low mana pool and depends on it to cast Reincarnation. Mana Drain will render him useless.
* Wraith King has very low mobility, making it easy for Lion to disable and harass him.
Additional:
* While not being able to confront Wraith King by himself, Lion's Mana Drain helps in draining Wraith King's mana, preventing him from reincarnating unless he has his Aghanim's Shard.
* Lion's Earth Spike and Hex provide decent lockdown against Wraith King as well, preventing the latter from benefiting from Vampiric Spirit bonuses.

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

* Heroes with single-target abilities will be overwhelmed by Lycan and his summons: Wraith King, Bane, Phantom Assassin.

* Heroes with summons and illusions such as Broodmother and Naga Siren, are ill-suited for Wraith King to fight, as he has no source of waveclear.

* Heroes with area dispel can kill multiple skeletons at once: Brewmaster, Oracle.

* 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.

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

* Jakiro's area-of-effect abilities make him strong against heroes who rely on illusions and summons: Terrorblade, Naga Siren Chaos Knight, Phantom Lancer, Broodmother, Nature's Prophet, Lycan, Wraith King.

* Many physical-only single-target heroes like Lifestealer, Sven, Wraith King, Phantom Assassin, Templar Assassin can have their damage mitigated by Cold Embrace.

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

* Heroes who can delivers a big chunk of damage in few hits will find themselves struggle against Templar Assassin's Refraction: Sven, Phantom Assassin, Ursa, Wraith King, Lifestealer

* Nethertoxin disables Bulwark entirely, making Mars far less tanky. Using Nethertoxin inside Arena of Blood may discourage enemies from following up with Mars' initiation.
* Rod of Atos is currently common on Viper and keeps Mars in position long enough to be killed.
* Beware that Viper is not very tanky earlier in the game, so positioning against Mars is important since a well-timed Spear of Mars can be the end of Viper.
Additional:
* 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.

* Melee heroes with low mobility can be kited and killed by Viper: Treant Protector, Kunkka, Alchemist, Troll Warlord, Wraith King, Tiny, Sven.

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

* 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 on physical damage are easily negated by Ghost Shroud: Phantom Assassin, Wraith King, Juggernaut.

* Heroes which rely exclusively on right clicks will struggle somewhat against Blinding Light: Phantom Assassin, Wraith King, Medusa

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

* Broodmother can easily clear Wraith King's skeletons with Spawn Spiderlings and summon spiderlings in their place.
* With Diffusal Blade, Broodmother can prevent Wraith King from reincarnating unless Wraith King has his Aghanim's Shard.

* Mana Break quickly eats away at Wraith King's small mana pool, preventing Reincarnation from triggering.
* Wraith King has no innate mobility. Even with Blink Dagger, Wraith King is easily kited by Blink.
* Anti-Mage can farm much more quickly than Wraith King, allowing Anti-Mage to overpower Wraith King once a significant farm advantage is established.
Additional:
* Mana Break can prevent Wraith King from reincarnating unless Wraith King has his Aghanim's Shard that removes the mana cost from Reincarnation.
* With Manta Style, his mana burning will triple because illusions can also use Mana Break.

* Diffusal Blade lets Phantom Lancer drain Wraith King's mana, preventing Reincarnation from triggering until he buys an Aghanim's Shard.
* Wraith King is bad against illusions-based heroes, as Wraithfire Blast is his only single-target disable and can get overwhelmed easily.
* Doppelganger can disjoint Wraithfire Blast.
Additional:
* Doppelganger disjoints Wraithfire Blast.
* Wraith King is not good at handling illusion-based heroes, as his only disable is single-target.
* Phantom Lancer tends to get Diffusal Blade, leaving Wraith King no mana to reincarnate.

* Even though Wraith King can easily get a chance to retaliate with Reincarnation after Luna uses Eclipse against him, smart Luna can also turn Reincarnation against him by using Eclipse right after Reincarnation triggers and gets on cooldown, giving Luna an element of surprise she can use against Wraith King.
* Moon Glaives can be used to clear the waves of Wraith King's skeleton warriors summoned from Vampiric Spirit.
Additional:
* Even though Wraith King can easily get a chance to retaliate with Reincarnation after Luna uses Eclipse against him, smart Luna can also turn Reincarnation against him by using Eclipse right after Reincarnation triggers and gets on cooldown, giving Luna an element of surprise she can use against Wraith King.
* Moon Glaives can be used to clear the waves of Wraith King's skeleton warriors summoned from Vampiric Spirit.

* 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 even with early Bulwark points it deal so much damage and slow that Mars is forced to back off from the lane and play defensively every time the spell is used.
* Worth noting is 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.