* Troll Warlord can't switch targets at will, in order to build Fervor stacks, which makes it easy to use Decrepify in order to save allies
* During Battle Trance, Pugna can easily use Nether Blast, Decrepify and Life Drain on him

* 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.

* Troll Warlord's high attack speed means Counter Helix will proc extremely frequently even without creeps near him. This, combined with a Blade Mail means Axe can easily solo kill Troll Warlord even in later stages of the game.
* Battle Trance does not save Troll Warlord from a Culling Blade.
Additional:
* Troll Warlord has significant attack speed due to Fervor and Battle Trance, giving Axe a higher chance to proc Counter Helix and seriously injure Troll Warlord due to his relatively low maximum health.
* Axe often purchases Blade Mail, which can help Axe turn Troll Warlord's farm and high physical damage against him. The bonus armor provided by Berserker's Call means that Troll Warlord will take a lot more damage than Axe.
* Culling Blade is still capable of killing Troll Warlord during Battle Trance if his HP is low enough.

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

* Atrophy Aura decreases Troll Warlord's damage.
* Pit of Malice helps lock down Troll Warlord.
* Battle Trance disallows Troll from running out of both Firestorm and Pit of Malice.

* 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.

* Fate's Edict can disarm Troll, rendering him useless in a teamfight, especially if he has already used Battle Trance.
* Fortune's End and Purifying Flames can provide ample magic damage to help burst down Troll Warlord quickly in the early to mid game.
* False Promise can save an ally from Troll Warlord's initiation, forcing him to switch targets and lose his Fervor stacks, or waste time during Battle Trance.

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

* Heroes with mediocre health pools who rely on armor or evasion to survive fights such as Troll Warlord, Windranger, and Terrorblade can be killed by Zeus if caught off guard.

* 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.

* Any heroes with low mana pools will die quickly or even instantly to Sanity's Eclipse: Doom, Phantom Assassin, Troll Warlord.

Additional:
* Outworld Destroyer's pure damage from Arcane Orb is very effective at killing Troll Warlord quickly.
* Astral Imprisonment removes Troll Warlord from a fight for four seconds, minimizing his contribution to a teamfight, and potentially wasting over half of Battle Trance's duration.
* Troll Warlord gains a measly 1 intelligence point per level, meaning Sanity's Eclipse is especially effective, often instantly killing him.

* 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.

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

* 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.

* Dark Willow's burst damage and stun prevents Troll Warlord from approaching her until he has Black King Bar.
* Troll Warlord's lack of burst damage makes it hard for him to kill Dark Willow before she slips into Shadow Realm.

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

* Timber Chain can kite Troll Warlord extremely effectively.
* Whirling Death and Chakram deals lots of damage to Troll Warlord.
* Reactive Armor makes Timbersaw extremely resilient to Troll's attack damage and extreme attack speed, especially during Battle Trance.

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

* Low-health, normally mobile carries who rely entirely on raw attack damage are vulnerable to Bane's nukes and disables: Anti-Mage, Clinkz, Drow Ranger, Faceless Void, Gyrocopter, Juggernaut, Meepo, Mirana, Monkey King, Morphling, Phantom Assassin, Phantom Lancer, Riki, Shadow Fiend, Slark, Sniper, Terrorblade, Troll Warlord, Weaver.

Additional:
* Nightmare and Fiend's Grip help to control/disable Troll Warlord in team-fights.

* 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.

* 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 with high physical damage output but lack of reliable escape mechanisms are always a good target for a solo gank: Sniper, Shadow Fiend, Troll Warlord, Drow Ranger. Those heroes, however, are dangerous if they manage to close the gap, so take caution.

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

* Shadow Shaman's long disables are effective at kiting and wasting the duration of Battle Trance.
* Mass Serpent Ward are especially effective against Troll Warlord during Battle Trance, as trapping him inside them during the duration is effectively another hard disable, as Troll cannot attack the wards or use Phase Boots to escape.

* 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.
Additional:
* 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.

* Cold Embrace can protect Troll Warlord's target, especially during Battle Trance.
* Winter's Curse can turn Troll Warlord's high physical damage and attack speed against his allies.
Additional:
* Cold Embrace will protect your ally from being damaged if he gets focused by Troll, although be careful as Fervor will keep gaining stacks even while Cold Embrace is active.
* Fervor works on allies.
* His high attack speed will help to kill his cursed ally faster.

* 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.

* 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.

* 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.

* 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.

* 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.

* Troll Warlord is very susceptible to Pierce the Veil due to having low health and reliance on high armor.
* Troll Warlord's ultimate Battle Trance can simply be ignored by using Pierce the Veil.
* Troll Warlord's Rampage buff for allies can easily be countered by The Calling which will lower their attack speeds back to normal.

* 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.

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

* 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.

* Primal Roar and the slow from Boars make kiting Troll Warlord very easy.

* Static Link is effective against Troll Warlord, as he mainly relies on attack speed more so than damage.
* Static Link is even more effective if Troll Warlord used Battle Trance, as he has no way to break the link.
Additional:
* Static Link can drain most or all of Troll Warlord's damage, making him useless in a teamfight or unable to last hit in lane. This is especially effective during Battle Trance, because Troll has no option to cancel the link.
* Storm Surge allows Razor to chase after or run away from Troll Warlord while doing damage with Eye of the Storm.

* 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.

* 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.

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

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

* Jakiro's reliance on his abilities can cause struggles for heroes who rely on evasion or blinds to get upper hand: Phantom Assassin, Windranger, Riki, Troll Warlord, Keeper of the Light.

* Phantasm gives Chaos Knight a significant advantage against single-target damage dealers: Lifestealer, Wraith King, Night Stalker, Troll Warlord.

Additional:
* Chaos Knight's tanky illusions easily take advantage of Troll Warlord's lack of AoE damage.
* Chaos Bolt can stun Troll for up to 4 seconds and Reality Rift prevents Troll Warlord from chasing down foes.
* Phantasm increases Chaos Knight's physical damage output up to 4 times and can easily kill Troll Warlord before he has a chance to use Battle Trance or a Black King Bar.

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

* With Aghanim's Scepter upgraded Infest, Lifestealer can use it on enemy heroes to attack them and disarm them from inside, even if they are spell immune, which can give him the edge over the heroes he's weak against like Ursa, Phantom Assassin, Terrorblade or Troll Warlord.

* 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.

* Troll Warlord's high speed attack makes Retaliate deal a lot of damage to him.

* Heroes who rely heavily on melee attacks and lack early spell immunity are easily blocked and interrupted by Ink Swell: Lycan, Ursa, Troll Warlord.

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

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

* In general, Brewmaster's Cinder Brew and Thunder Clap makes him good against physical damage carries: Ursa, Clinkz, Faceless Void, Troll Warlord, Templar Assassin, Phantom Assassin.

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

* Other heroes that rely on physical attacks to deal damage and not their abilities: Troll Warlord, Sniper, Monkey King, Sven.

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

* Heroes that rely on physical damage are ineffective against Dragon Knight due to his high armor: Phantom Assassin,Bloodseeker, Lifestealer, Troll Warlord, Sven

* 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.

* Bulwark is generally irrelevant against Riki as he primarily deals bonus damage from behind.
Additional:
* 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.

* Frost Blast and Chain Frost can kite Troll Warlord effectively.
* Frost Shield can single-handedly waste most of the duration of Battle Trance, due to the extreme resistance to physical damage Frost Shield provides. In addition, Troll Warlord is incapable of switching targets during Battle Trance, so he cannot pick an easier target.
* Troll Warlord has little to no ability to regenerate HP, so Frost Blast together with Frost Shield can harass him effectively.

* Frostbite can disarm and root Troll Warlord if he doesn't have a Black King Bar or a Manta Style to dispel it.
* Crystal Nova and Freezing Field both significantly slow Troll Warlord, making him much more vulnerable to ganks or stuns.
* The magical damage from Freezing Field does a large amount of AoE damage, and Troll Warlord is not capable of cancelling Crystal Maiden's channel.

* 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.

* 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.

* Melee heroes who may struggle to get close to Sniper: Wraith King, Kunkka, Doom, Tidehunter, Underlord, Troll Warlord, and etc.

Additional:
* Shrapnel and Headshot allows Sniper to kite Troll Warlord effectively.
* Take Aim together with certain items such as Hurricane Pike allow Sniper to sit and fire at Troll Warlord from a safe distance.

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

* 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.

* With Bloodthorn, Clinkz becomes a strong counter to heroes who rely on evasion and blind such as Windranger, Phantom Assassin, Troll Warlord and Keeper of the Light.

* Clinkz, Sniper, Lone Druid, Troll Warlord, Legion Commander and Wraith King are some of the Heroes that base themselves on attacks with little or no spell power, so they suffer in the grassy hands of Overgrowth.