* Charge of Darkness can be used to escape or counter-initiate against a Relocate gank.
* Greater Bash and Nether Strike is devastating due to Io's low armor, and can even knock it away from tethered target.

* Quill Spray is very effective against Io, as it has very low armor and has to stay close to the fight to not break its Tether.

* Spirit Breaker can chase Nature's Prophet from anywhere on the map with Charge of Darkness, making it hard for Nature's Prophet to split-push.
* Charge of Darkness and Nether Strike gives vision of Nature's Prophet when he tries to Sprout himself and teleport away.
Additional:
* Charge of Darkness allows Spirit Breaker to catch Nature's Prophet out when he tries to split push.
* Nature's Prophet can't hide in his Sprout against Spirit Breaker, as his Charge of Darkness provides vision on its target.
* Spirit Breaker can easily cancel Nature's Prophet's Teleportation.

* Heroes that have AoE damage: Lina, Keeper of the Light, Timbersaw, Leshrac, Bristleback, Axe

* Charge of Darkness provides shared vision over its target, keeping track of heroes who rely on invisibility, mobility, or illusions: Riki, Broodmother, Phantom Lancer

* Bristleback's tankiness and damage reduction from the rear makes him very hard for Phantom Lancer to chase and finish off, due to his lack of burst damage.
* Quill Spray quickly destroys Phantom Lancer's illusions.
* Bristleback's passive costs no mana, meaning that it will continue to trigger even if Phantom Lancer drains Bristleback's mana with Diffusal Blade.
Additional:
* Bristleback's tankiness and damage reduction from the rear makes him very hard for Phantom Lancer to chase and finish off, due to his lack of burst damage.
* Quill Spray destroys Phantom Lancer's illusions.
* Bristleback's passive costs no mana, meaning that it will continue to trigger even if Phantom Lancer drains Bristleback's mana with Diffusal Blade.

* Spirit Breaker's Charge of Darkness semi-reveals Bounty Hunter, taking away his element of surprise for the duration of the charge. Also, as Charge of Darkness shows Bounty Hunter's position, Spirit Breaker's allies can proceed to gank Bounty Hunter while he is roaming alone.

* Bristleback's Viscous Nasal Goo can catch and slow Bounty Hunter. Warpath and Quill Spray can defeat him quickly due to his small HP pool when compared to Bristleback's.

* Spirit Breaker's stuns pierce spell immunity, making him a good choice against heroes that heavily rely on Black King Bar; Huskar

* The damage from Burning Spear can be reduced by turning away from Huskar.
* Bristleback can bait Huskar into using Life Break on him, then turn around and receive very little damage.
Additional:
* Bristleback's tankiness and Bristleback allow him to outlast Burning Spears' damage-over-time at almost any point in the game. In addition, if Huskar chooses to cast Life Break on Bristleback, Bristleback can simply turn around before it hits and receive little damage.
* Viscous Nasal Goo will reduce Huskar's low armor even further, and Quill Spray and Warpath will tear him down extremely quickly.

* Charge of Darkness provides shared vision over its target, keeping track of heroes who rely on invisibility, mobility, or illusions: Riki, Broodmother, Phantom Lancer

* Quill Spray destroys spiderlings, and hits Broodmother even when she's regenerating in her webs. This makes Bristleback one of her hardest counters in lane.
Additional:
* Bristleback reduces most of Broodmother's and her spiderlings' damage.
* Quill Spray will hit any spiders in its proximity, hindering Broodmother's fighting and farming capabilities.

* Charge of Darkness provides shared vision over its target, keeping track of heroes who rely on invisibility, mobility, or illusions: Riki, Broodmother, Phantom Lancer

* Quill Spray will hit Riki even when he is invisible.
* Cloak and Dagger's bonus backstab damage is rendered irrelevant against Bristleback.
* Smoke Screen does not stop Bristleback's passive from activating.
* Due to Bristleback's natural tankiness, he is an ideal Gem of True Sight carrier, directly countering Riki's invisibility.
Additional:
* The bonus Backstab damage from Cloak and Dagger is rendered irrelevant with Bristleback and hurts Riki more than him because of the passive Quill Spray.
* Riki can still get damaged by Bristleback's Quill Spray while invisible, and it can be hard to deal with in lane.
* Bristleback is not too bothered by Smoke Screen. Though he cannot use Quill Spray manually inside it, it still procs passively when he takes damage from the back. The movement speed from Warpath allows him to get out of the area easily.
* Due to Bristleback's natural tankiness, he is an ideal Gem of True Sight carrier.
* Riki rarely buys Silver Edge to break Bristleback's passive because the invisibility aspect of it is redundant.

* Bristleback, Centaur Warrunner, Spirit Breaker, Pudge, Huskar: These heroes are too tanky for Puck to burst down. Also, all of them have spells which can deal with and shut Puck down reliably.

* Bristleback, Centaur Warrunner, Spirit Breaker, Pudge, Huskar: These heroes are too tanky for Puck to burst down. Also, all of them have spells which can deal with and shut Puck down reliably.

* Spirit Breaker can charge towards Sniper from anywhere on the map with Charge of Darkness.
* Greater Bash deals magical damage, which can prove dangerous to Sniper and his low health.
* Both previous abilities combined with Nether Strike ensures that Spirit Breaker can easily solo kill Sniper.

* Bristleback's abilities are nearly useless for Rubick to Spell Steal, as he does not gain the bonuses from Warpath.
Additional:
* Rubick deals little damage on his own, and Bristleback can simply shrug off all his spells and chase Rubick down with his Quill Spray and the damage bonus from Warpath.
* Rubick does not tend to charge forward in teamfights, stay in the front lines under most circumstances, yet effective casts of Quill Spray and Viscous Nasal Goo requires the opposite as they require multiple casts and close range to add up stacks.
* Rubick does not benefit from Warpath through casting the stolen spell.

* Quill Spray quickly destroys Chaos Knight's Phantasms.

* Charge of Darkness can be used to chase down Pangolier if he escapes with Swashbuckle or Rolling Thunder.
* Nether Strike ignores Rolling Thunder's spell immunity, and will still hit Pangolier if he rolls or dashes away.

* Charge of Darkness allows Spirit Breaker to gank Shadow Fiend in the early game, preventing him from getting Necromastery stacks.
* Nether Strike and Charge of Darkness can be used to prevent Shadow Fiend from casting Requiem of Souls.

* Tiny's nonexistent armor in the early game makes him very vulnerable to Quill Spray's large amounts of physical damage.
* Bristleback decreases Tiny's high burst damage against Bristleback.
* Viscous Nasal Goo can slow Tiny to a crawl and allows Bristleback to easily kite him with his high movement speed and Quill Spray's long range, as Tiny has no ability to escape.

* Bristleback is one of the hardest heroes to gank with a Meat Hook and Dismember combo, and attempts to do so sometimes backfire on Pudge.
Additional:
* Pudge is particularly susceptible to Bristleback's Viscous Nasal Goo and Quill Spray due to his naturally low armor and poor agility gain.
* Bristleback, in combination with his strength gain, high health, common itemization for magic resistance and damage reduction from Bristleback makes him a poor target for Pudge.

* Magic Missile has a considerably long cast time, making it difficult to stop Charge of Darkness with it.
* Other than Magic Missile, Vengeful Spirit has no way of canceling Nether Strike.

* Quill Spray will hit Sand King inside Sand Storm, damaging him and putting Sand King's Blink Dagger on cooldown, preventing him from escaping.
* Epicenter's numerous damage ticks will trigger Bristleback's passive repeatedly during teamfights.

* Fortune's End cannot dispel Warpath stacks on Bristleback or Quill Spray stacks on allies.
* Bristleback can heavily reduce Oracle's damage output. With it, Oracle may accidentally heal Bristleback with Purifying Flames, especially if Bristleback has bonus magic resistance.

* Possibly Clinkz's worst enemy. He has many tools to utterly destroy Clinkz.
* Charge of Darkness can be used on Clinkz if Spirit Breaker's team spots him anywhere. This charge will track his location through Skeleton Walk's invisibility and movement speed bonuses.
* When Spirit Breaker charges onto Clinkz, he can easily use Dust of Appearance to guarantee a reveal on him while stunned.
* All three of Spirit Breaker's spells help him and his team quickly close the gap to Clinkz even at the edge of his attack range or when running away with Skeleton Walk.
* Spirit Breaker's high strength and above average armor makes him able to endure Clinkz's onslaught, meanwhile Clinkz will be heavily threatened if Spirit Breaker procs a Greater Bash.
Additional:
* Once caught with dust, Clinkz could be locked down for a long time by Spirit Breaker and has nowhere to escape.
* Charge of Darkness provides shared vision over its target, showing Clinkz even when he is in Skeleton Walk.

* Lone Druid and The Spirit Bear cannot burst down Bristleback due to Bristleback
* Bristleback can easily run to Lone Druid without any hesitation, with Viscous Nasal Goo to reduce armor and slow the Spirit Bear or Lone Druid and Quill Spray can deal damage to both Lone Druid and the Spirit Bear at the same time

* Tinker relies on his high mobility from Boots of Travel and Blink Dagger to survive. Those items don't help him if Spirit Breaker manages to cast Charge of Darkness on him.
* Spirit Breaker can easily cancel Rearm and Boots of Travel.

* Lycan's wolves deal little damage to Bristleback, and are easily killed by Quill Spray, even when they're invisible.
* Lycan's lack of burst damage makes it very hard for him to kill Bristleback, especially when his back is turned.
Additional:
* Quill Spray can be used to kill Lycan's summons.
* Bristleback allows him to stay alive against Lycan while dishing out counter attacks
* He can overpower Lycan with his Warpath instead.

* Heroes that rely on escapes to stay alive can be caught and locked down for a long time: Queen of Pain, Phantom Assassin

* Because Templar Assassin does not have escape potential in lane, any support hero with roaming potential and a Dust of Appearance can be great at shutting her down early game: Earth Spirit, Spirit Breaker, Tusk, Bounty Hunter, Riki, Warlock.

* Heroes with high physical damage can damage Lifestealer more than he can heal: Bristleback, Clinkz, Luna,Shadow Fiend, Slardar, Terrorblade

* Heroes with long range abilities are also able to touch Zeus, such as Clockwerk, Kunkka, Puck, Skywrath Mage, Spirit Breaker, Tusk and others.

* Warlock is a very strong hero when positioned correctly, and his long cast range helps him with this. However, some Heroes might disrupt or sneakily pass through his allies and deal with him, preventing him from doing his job. Such heroes include Chaos Knight, Spirit Breaker, Riki, and more.

* Generally, heroes that can close the gap on Drow Ranger to cancel her Marksmanship such as Phantom Assassin, Spirit Breaker, and Tusk are effective at limiting her power and bursting her down.

* Heroes with long-lasting, undispellable debuffs will pinpoint the true Naga Siren: Spirit Breaker, Bloodseeker.

* Heroes that rely on invisibility can be tracked with Charge of Darkness opening them to team attacks: Bounty Hunter, Mirana, Riki

* Heroes who can stun multiple units at once: Dark Willow, Spirit Breaker, Slardar, Invoker, and Tidehunter.

* Quill Spray usually hits Meepo's clones, although Bristleback cannot turn his back when rooted with Earthbind.

* Viscous Nasal Goo can hinder Crystal Maiden's already abysmal mobility, which allows Bristleback (or his teammates) to run her down and kill her.
* Bristleback frequently builds Blade Mail, which can quickly kill Crystal Maiden if her ultimate is used while he is under its effect.
* The passive part of Bristleback will trigger many, many times under the damage from Freezing Field, and as the stacks increase, the damage output from each successive cast (or proc) will eat away at Crystal Maiden's small HP pool.

* Multiple instances of damage from Eclipse will trigger Bristleback's passive repeatedly in a short time, dealing tremendous damage to Luna and her teammates.
Additional:
* Quill Spray and Bristleback harass Luna more efficiently than she does with Lucent Beam.
* Bristleback helps return a lot of damage to Luna’s team if she uses her nukes on him and he has his back to her.
* Viscous Nasal Goo and Warpath are enough to outrun a speedy Luna.
* Bristleback tends to be a frequent carrier of Crimson Guard, which is good protection from bouncing glaives.

* Bristleback's constant harass from Quill Spray will greatly hurt Enigma's laning and kill his Eidolons.
* However, Bristleback has no way of canceling Black Hole at all. And Bristleback is not a hero that goes for disabling items to counter that problem.

* Arc Warden has relatively lower armor and mobility, which makes him an easy target to apply Quill Spray and Viscous Nasal Goo stacks.
* Arc Warden also does not like to build a Silver Edge as it takes a long time to build up and may slow down the timings for other important items needed in the game like Gleipnir.
* However, do note that in a game where Arc Warden's team has many jumping capabilities or good passives, like a Tidehunter or Spectre, a Silver Edge becomes incredibly valuable on Arc Warden as not only can he run away from the jumps, he effectively gets 2 breaks, and Bristleback may not be the best pick.

* Unlike with other heroes who can summon illusions of themselves, Terrorblade's illusions from Conjure Image have different colors than other illusions which can be seen even by enemy team, which can also make Terrorblade weak even against heroes he naturally counters: Bane, Lifestealer, Spectre, Chaos Knight, Spirit Breaker, Sniper. Terrorblade's only solution to counter this problem is to get Manta Style as quickly as possible.

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

* Heroes that rely on escapes to stay alive can be caught and locked down for a long time: Queen of Pain, Phantom Assassin

* Heroes with mobility/escape mechanisms to dodge Ancient Apparition abilites, or to easily jump on him: Riki, Queen of Pain, Phantom Assassin, Windranger, Bounty Hunter, Spirit Breaker, Night Stalker, Storm Spirit, Juggernaut, etc.

* Heroes with damage-over-time abilities will not only proc Bristleback's passive continuously, they will also do little harm to him when he is facing away from the source: Venomancer, Arc Warden

* Macropyre's frequent damage ticks causes Bristleback to activate repeatedly, resulting in free damage as long as Bristleback faces away from Jakiro.

* Quill Spray's constant AoE damage will hit Dark Willow even in Shadow Realm. Its automatic damage will hurt her if she tries to get close and use Bedlam.

* Anti-Mage usually relies on Blink to escape, but with vision from Charge of Darkness it is easier to catch him.
* Spirit Breaker could single-handedly lock Anti-Mage down for 4 seconds (or even more with lucky bashes), allowing his teammates to follow up.
* As Anti-Mage is an elusive hero who likes to farm alone, Spirit Breaker could choose to charge whenever Anti-Mage is in sight.