Dark Seer
* 
Fortune's End dispels Ion Shell and Surge, making any gank attempt on Dark Seer in the laning phase likely to succeed.
* 
Fate's Edict prevents all magical damage that comes from Dark Seer's abilities.
* Fortune's End dispels Ion Shell on creeps, which Dark Seer relies on to farm and zone.
Additional:
* Fortune's End can dispel 
Ion Shell, a skill that helps Dark Seer immensely in the laning phase, as well as 
Surge, a move-speed buff, effectively allowing Oracle to control Dark Seer, especially in the laning phase.
Dazzle
* 
Shallow Grave prevents Ice Blast's shatter for up to 5 seconds, but can mostly only delay it as Ice Blast's debuff lasts 10 seconds and prevents 
Shadow Wave from healing them.
Additional:
* 
Ice Blast negates healing from Shadow Wave, and lasts longer than Shallow Grave.
Dazzle
* 
Astral Imprisonment is a versatile nuisance:
* If it is cast on a low-enough-health unit at least 1 second into Shallow Grave's duration, the Shallow Grave will end during the imprisonment, and the target will take lethal damage when released.
* It can be used remove Dazzle from the fight at a time he could have saved someone.
* It lets himself or an ally dodge all of Poison Touch's effects, for long enough to recover their 
Blink Dagger.
Dazzle
* A well-timed 
Global Silence prevents Dazzle from saving allies with Shallow Grave or Shadow Wave. Items that could dispel the silence are expensive, and difficult for Dazzle to farm from a support role.
* 
Arcane Curse and 
Last Word cause long damage over time, which may outlast Shallow Grave.
Dazzle
* Culling Blade ignores the protection from Shallow Grave and will kill any target whose health is low enough. This makes Axe one of the hardest counters to Dazzle, and he neutralizes one of Dazzle's most important abilities.
Additional:
* 
Culling Blade kills any target under the health threshold, even through Shallow Grave.
Dazzle
* Pugna can turn out to be an effective hero against Dazzle due to the fact that he does not allow him to extend his 
Poison Touch with his 
Decrepify, which is why Dazzle cannot keep the enemy under prolonged deceleration.
* Pugna has a very strong ability against casters with a small health reserve - 
Nether Ward, which is why heroes like Dazzle will not be able to constantly throw their Poison Touch 
Bad Juju and Shadow Wave at enemies under the action of Nether Ward or will be forced to take a lot of damage
Additional:
* Pugna can turn out to be an effective hero against Dazzle due to the fact that he does not allow him to extend his Poison Touch with his Decrepify, which is why Dazzle cannot keep the enemy under prolonged deceleration.
* Pugna has a very strong ability against casters with a small health reserve - Nether Ward, which is why heroes like Dazzle will not be able to constantly throw their Poison Touch Bad Juju and Shadow Wave at enemies under the action of Nether Ward or will be forced to take a lot of damage
Dark Seer
* 
X Marks the Spot prevents Dark Seer or his allies from escaping with Surge.
Dark Seer
* 
Flame Guard makes Dark Seer not deal any damage with his skills to Ember Spirit.
Dark Seer
* A Sniper who is somewhat competent at positioning is hardly going to be affected by any of Dark Seer's spells thanks to 
Take Aim.
* However, an illusion of Sniper made with Wall of Replica is extremely powerful, and hard to deal with.
Dark Seer
* 
Spell Steal will easily steal all abilities from Dark Seer.
Additional:
* Spell Steal can perfect from Rubick's steal all abilities from Dark Seer. Rubick's always purchase 
Aghanim's Scepter can two stolens abilities from Dark Seer's and waiting for seconds for second stolen abilities (example: combinated Vacuum and Wall of Replica) and many different combination.
* A good positoning from Rubick's Spell Steal waiting steal abilities from Dark Seer 
Wall of Replica and illusion from Wall of Replica Dark Seer's can fighting with effect from outcome steal Wall of Replica from Rubick's.
* Combinated Rubick's steal Surge and Blink Dagger is very important catch from Dark Seer's and enemies.
* Rubick's 
Telekinesis can lifted up Dark Seer or enemy heroes and throw to Wall of Replica from Rubick's steal.
Dark Seer
* The constant dispel from Demonic Purge will make any attempt to save the victim or himself by Surge become futile. For what it's worth, Demonic Purge will also dispel Ion Shell.
Dazzle
* Doom can completely shut down Dazzle through 
Doom, as it prevents him from casting his abilities and, by extension, gaining Bad Juju stacks.
Dark Seer
* Dark Seer relies on Surge for most of his mobility, so he's not very vulnerable to slows, but much more to root effects and walls or pseudo-walls such as 
Disruptor's 
Kinetic Field or 
Slark's 
Pounce.
Dazzle
* Some heroes with extreme range, like 
Zeus, 
Invoker or 
Clockwerk, can snipe your allies from anywhere after your Grave has expired.
Dazzle
* Heroes with high burst damage through their physical attacks or spells can kill Dazzle or his allies before he has a chance to use Shallow Grave. (
Lina, 
Lion, etc.)
Dazzle
* Some heroes with extreme range, like Zeus, Invoker or Clockwerk, can snipe your allies from anywhere after your Grave has expired.
Dark Seer
* Abilities that deal low damage with high amounts of instances are irrelevant against Pudge during Flesh Heap's active: 
Gyrocopter's 
Rocket Barrage and 
Dark Seer's Ion Shell are just a couple examples.
Dark Seer
* Dark Seer's only disable is Vacuum. Though he starts off with high armor and health, he'll eventually have a hard time dealing with high mobility heroes such as 
Weaver or 
Queen of Pain.
Dark Seer
* Dark Seer's only disable is Vacuum. Though he starts off with high armor and health, he'll eventually have a hard time dealing with high mobility heroes such as Weaver or Queen of Pain.
Dark Seer
* Strong laners are usually at a disadvantage because of how well Sven can jungle. Heroes such as Dark Seer. 
Underlord and 
Legion Commander may find that later Sven takes care of them very quickly after some jungle farming.
Dark Seer
* In general, heroes who are melee with no way to fight back can be very easily poked by Monkey King to gain his Jingu Mastery stacks: Dark Seer, 
Riki, 
Rubick.
Dazzle
* Heroes with high burst damage through their physical attacks or spells can kill Dazzle or his allies before he has a chance to use Shallow Grave. (Lina, Lion, etc.)
Additional:
* Laguna Blade can kill Dazzle quickly before he casts Shallow Grave.
Dazzle
* 
Juxtapose and 
Doppelganger conjures too many illusions for Dazzle to deal with, given he has no inherent movement- or AoE-abilities.
* However, this can be partially solved with 
Aghanim's Shard-upgraded Poison Touch, as the hex instantly destroys illusions in an area as well as revealing the real Phantom Lancer when he's hiding among his army of illusions.
* 
Phantom Rush and 
Spirit Lance allow Phantom Lancer to trivially catch Dazzle even in the back line of a fight.
* Phantom Lancer has high base armor which counters Dazzle's physical damage based spells in lane.
* 
Diffusal Blade, a core item on Phantom Lancer, drains mana, which can be a problem for Dazzle, as all of his abilities have a high mana cost.
Dark Seer
* Heroes that rely on illusions typically spawn very strong illusions inside Dark Seer Wall of Replica that he can use against them or their team: 
Phantom Lancer, 
Chaos Knight, 
Naga Siren, 
Terrorblade.
Additional:
* Ion Shell helps taking down illusions quickly, making it easy to identify the real Phantom Lancer.
* Surge allows Dark Seer and his teammates to run away from Phantom Lancer, who relies on his Phantom Rush to chase enemies.
Dazzle
* 
Bloodseeker's 
Thirst, 
Rupture, and huge AoE silence 
Blood Rite can fare well against Dazzle.
Dark Seer
* Heroes with fast movement abilities will suffer huge damage when afflicted by Rupture: 
Spirit Breaker, 
Earth Spirit, Dark Seer.
Additional:
* Rupture can deal a lot of damage to either a surged Dark Seer or his allies and prevent the target from getting into position.
Dazzle
* Shallow Grave prevents Bloodseeker from replenishing his health by finishing off enemies.
Dazzle
* Poison Touch severely slows down Chen, deals damage over time and weakens his armor every time he gets attacked by Dazzle or any of his allies. Aghanim's Shard upgraded Poison Touch can hex Chen and prevent him from saving his allies with 
Hand of God.
* Neither Chen nor his converted creeps have burst damage at all, so Dazzle will always have plenty of time to save his allies with Shallow Grave.
* Dazzle can use Shadow Wave can heal his allies, kill Chen's creeps and damage Chen himself.
* Bad Juju can weaken Chen's armor, and the armor of his creeps every time Dazzle casts a spell while strengthening armor of Dazzle's allies.
Dark Seer
* Dark Seer's 
Vacuum and Ion Shell can clear a wave of Chen's Creeps effectively.
* Surge applies haste movement and negates the slow from 
Penitence, allowing Dark Seer to easily escape from Chen and his creeps.
* Dark Seer's full combo from Dark Seer's Vacuum, Wall of Replica and 
Normal Punch from Aghanim's Scepter can often kill Chen or any of his allies before he can save them with Hand of God.
Additional:
* Dark Seer's Vacuum and Ion Shell can clear a wave of Chen's Creeps effectively.
* Surge applies haste movement and negates the slow from Penitence, allowing Dark Seer to easily escape from Chen and his creeps.
* Dark Seer's full combo from Dark Seer's Vacuum, Wall of Replica and Normal Punch from Aghanim's Scepter can often kill Chen or any of his allies before he can save them with Hand of God.
Dazzle
* Aghanim's Shard upgraded Poison Touch can be used to easily kill many of Terrorblade's illusions from both 
Conjure Image and 
Manta Style, it can also hex the real Terrorblade, silencing him, disarming him, slowing him, muting him and rendering him unable to do anything at all.
* Shallow Grave can be used to save an ally whom Terrorblade has used 
Sunder on under the condition Dazzle is quick enough to do it. And since Terrorblade has no "real" burst damage potential outside from Sunder, Dazzle will usually have plenty of time to save an allied hero on which Sunder was used.
* Shadow Wave will always damage Terrorblade and his illusions whenever Terrorblade has no 
Metamorphosis available to use, while healing Dazzle's allies. Aghanim's Scepter upgraded Shadow Wave can also be used directly on Terrorblade, and bounce on both Terrorblade and his illusions alike, causing them to take damage and to be attacked by Dazzle. Shadow Wave can also pierce throught debuff immunity by 
Black King Bar, one of the items Terrorblade relies on to survive in teamfights.
* Bad Juju can weaken Terrorblade's armor every time Dazzle casts a spell while strengthening armor of Dazzle's allies.
Additional:
* Aghanim's Shard upgraded Poison Touch can be used to easily kill many of Terrorblade's illusions from both Conjure Image and Manta Style, it can also hex the real Terrorblade, silencing him, disarming him, slowing him, muting him and rendering him unable to do anything at all.
* Shallow Grave can be used to save an ally whom Terrorblade has used Sunder on under the condition Dazzle is quick enough to do it. And since Terrorblade has no "real" burst damage potential outside from Sunder, Dazzle will usually have plenty of time to save an allied hero on which Sunder was used.
* Shadow Wave will always damage Terrorblade and his illusions whenever Terrorblade has no Metamorphosis available to use, while healing Dazzle's allies. Aghanim's Scepter upgraded Shadow Wave can also be used directly on Terrorblade, and bounce on both Terrorblade and his illusions alike, causing them to take damage and to be attacked by Dazzle. Shadow Wave can also pierce throught debuff immunity by Black King Bar, one of the items Terrorblade relies on to survive in teamfights.
* Bad Juju can weaken Terrorblade's armor every time Dazzle casts a spell while strengthening armor of Dazzle's allies.
Dark Seer
* Dark Seer's Vacuum and Ion Shell allows him to clear a wave of Terrorblade's illusions.
* Because Terrorblade often builds items that require 
Ultimate Orb like Manta Style and 
Eye of Skadi, Dark Seer can create a very strong illusion of Terrorblade with Wall of Replica and Normal Punch from Aghanim's Scepter.
* If Dark Seer can use Vacuum to help teammates land their AoE abilities, Terrorblade will be quickly killed before he even gets a chance to use Sunder.
Additional:
* Dark Seer's Vacuum and Ion Shell allows him to clear a wave of Terrorblade's illusions.
* Because Terrorblade often builds items that require Ultimate Orb like Manta Style and Eye of Skadi, Dark Seer can create a very strong illusion of Terrorblade with Wall of Replica and Normal Punch from Aghanim's Scepter.
* If Dark Seer can use Vacuum to help teammates land their AoE abilities, Terrorblade will be quickly killed before he even gets a chance to use Sunder.
Dazzle
* Venomancer's damage-over-time abilities are easier to heal through with numerous Shadow Waves than other types of damage, and it's simple to time a Shallow Grave until the last possible second to save a teammate from them.
Dark Seer
* Venomancer is a low health hero and low range hero who is easy to harass with Ion Shell on a creep in the early game.
* Venomancer depends entirely on all his slows to keep distance or chase, but since Surge ignores slows, it is nearly impossible for Venomancer to hunt or run away from Dark Seer or his surged teammates.
Dazzle
* Heroes who rely on magical damage resistance may have a hard time laning against Dazzle as all of Dazzle's abilities deal physical damage instead of magical: 
Anti-Mage, 
Huskar, 
Viper.
Dark Seer
* Heroes who do not have nor rely on passive abilities make Nethertoxin much less effective: 
Clinkz, 
Pugna, 
Nature's Prophet, Dark Seer, 
Lycan, 
Tusk
Dazzle
* Once he buys Aghanim's Shard, Dazzle's Poison Touch can hex enemies, and hex can instantly kill illusions, making Dazzle strong against heroes who rely on illusions. Bear in mind that Chaos Knight is the exception because his 
Phantasms are strong illusions that are immune to abilities that can instantly kill illusions.
Dark Seer
* Heroes that rely on illusions typically spawn very strong illusions inside Dark Seer Wall of Replica that he can use against them or their team: Phantom Lancer, Chaos Knight, Naga Siren, Terrorblade.
Dazzle
* Heroes with armor reducing abilities greatly hinder Visage's defense like 
Slardar and 
Dazzle.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: 
Beastmaster, 
Broodmother, 
Enigma, Nature's Prophet, 
Visage, 
Warlock, 
Wraith King.
Dazzle
* Shallow Grave can prevent the death of an ally that is trapped inside the Chronosphere.
* Shadow Wave lets Dazzle heal allies and damage enemies from outside Chronosphere.
Dark Seer
* 
Living Armor can be destroyed quickly with Ion Shell.
Dazzle
* 
Reaper's Scythe is very predictable and gives Dazzle plenty of time to react with Shallow Grave: Dazzle just has to keep a close eye on his allies below 50% health.
* However, Dazzle must be sure to use Shadow Wave on that ally immediately after, or they will die from 
Heartstopper Aura when the Shallow Grave ends!
Additional:
* Dazzle's Shadow Wave is a spammable healing ability that spreads around his entire team, slowing the death of his teammates as effectively as Necrophos spreads damage to them.
* If not immediately, Shallow Grave delays his ally from gradually dying to Necrophos's abilities, especially Reaper's Scythe.
* However, bear in mind that Dazzle's Poison Touch, Shadow Wave and Bad Juju all deal physical damage, and Dazzle has no abilities to help him deal magical damage at all, which can cause problems for Dazzle to kill Necrophos if he uses Ghost Shroud to protect himself.
Dazzle
* Shallow Grave prevents Legion Commander from killing her opponents in Duels.
* Shadow Wave will heal an ally caught in a Duel, as well as dealing damage to Legion Commander.
Dazzle
* Dazzle easily breaks the position of Lone Druid and his 
Summon Spirit Bear with his Poison Touch, As it always hits from afar and prolongs the slowdown on the Summon Spirit Bear, which is why he cannot catch up with Dazzle and treat his master with 
Spirit Link
* Dazzle helps his team survive the physical attacks of the Summon Spirit Bear thanks to the treatment from Shadow Wave and armor from Bad Juju, which can enable his team to kill Lone Druid
* The Lone Druid Summon Spirit Bear has a small amount of armor at the start of the game, because of Mid Dazzle, it can very much break through it and prevent Lone Druid from gaining an advantage at the very beginning of the game, giving his team the opportunity to overtake Lone Druid on items for killing him, by type: 
Spirit Vessel
Additional:
* Dazzle easily breaks the position of Lone Druid and his Summon Spirit Bear with his Poison Touch, As it always hits from afar and prolongs the slowdown on the Summon Spirit Bear, which is why he cannot catch up with Dazzle and treat his master with Spirit Link
* Dazzle helps his team survive the physical attacks of the Summon Spirit Bear thanks to the treatment from Shadow Wave and armor from Bad Juju, which can enable his team to kill Lone Druid
* The Lone Druid Summon Spirit Bear has a small amount of armor at the start of the game, because of Mid Dazzle, it can very much break through it and prevent Lone Druid from gaining an advantage at the very beginning of the game, giving his team the opportunity to overtake Lone Druid on items for killing him, by type: Spirit Vessel
Dark Seer
* Ion Shell destroys 
Refraction's protection stacks in short time.
* Surge ignores the massive slow from 
Psionic Trap.
Dazzle
* Shadow Wave provides good sustain against Tinker's spammable abilities.
* Shallow Grave can stop Tinker from bursting down a target.
Dazzle
* Poison Touch allows Dazzle to harass both, Io and it's tethered target on lane. Aghanim's Shard upgraded Poison Touch can also hex both, Io and it's tethered target, preventing them from escaping with Relocate, and also disarming them, silencing them, muting them and rendering them helpless against Dazzle and his allies.
* Io's damage output is one of the weakest, therefore Dazzle will have plenty of time to save an ally with Shallow Grave from gank by Io and it's tethered target.
* Shadow Wave will always hit both, Io and it's tethered target if they are near the ally Dazzle uses Shadow Wave on, while healing Dazzle's allies near them. Aghanim's Scepter upgraded Shadow Wave can bounce on both, Io and it's tethered target, causing them both to take damage and to be attacked by Dazzle. And unlike Io who doesn't get healed while using Tether, Shadow Wave will always heal Dazzle no matter on which of his allies he uses it on.
* Bad Juju will cause both, Io and it's tethered target to lose armor every time Dazzle casts a spell while strengthening armor of Dazzle's allies.
Additional:
* Poison Touch allows Dazzle to harass both, Io and it's 
Tethered target on lane. Aghanim's Shard upgraded Poison Touch can also hex both, Io and it's Tethered target, preventing them from escaping with Relocate, and also disarming them, silencing them, muting them and rendering them helpless against Dazzle and his allies.
* Io's damage output is one of the weakest, therefore Dazzle will have plenty of time to save an ally with Shallow Grave from gank by Io and it's Tethered target.
* Shadow Wave will always hit both, Io and it's Tethered target if they are near the ally Dazzle uses Shadow Wave on, while healing Dazzle's allies near them. Aghanim's Scepter upgraded Shadow Wave allows Dazzle Shadow Wave directly on Io and it's Tethered target which can also bounce on both, Io and it's tethered target, causing them both to take damage and to be attacked by Dazzle. And unlike Io who doesn't get healed while using Tether, Shadow Wave will always heal Dazzle no matter on which of his allies he uses it on.
* Bad Juju will cause both, Io and it's tethered target to lose armor every time Dazzle casts a spell while strengthening armor of Dazzle's allies.
Dark Seer
* Dark Seer can take great advantage of 
Divided We Stand by putting an Ion Shell on a clone in order to harass them effectively.
* Vacuum can take a single Meepo and disable him for Dark Seer and his teammates to take out.
Dark Seer
* Heroes with haste can negate Enchant's slow: Weaver, Dark Seer, Lycan, 
Centaur Warrunner.
Dazzle
* 
Mirror Image's illusions can easily walk straight at Dazzle and attack him, due to Dazzle's lack of reliable AoE nukes or disables.
* 
Ensnare roots Dazzle or his allies, making it harder to stay in range of Dazzle's saving abilities.
* 
Song of the Siren can be used to initiate a fight with superior positioning, potentially zoning Dazzle's high-impact spells out of the fight.
Dazzle
* Dazzle can instantly destroy all of Naga Siren's illusions from Mirror Image with Aghanim's Shard upgraded Poison Touch used on her or any of her illusions.
Dark Seer
* Heroes that rely on illusions typically spawn very strong illusions inside Dark Seer Wall of Replica that he can use against them or their team: Phantom Lancer, Chaos Knight, Naga Siren, Terrorblade.
Dark Seer
* Certain heroes can mess up with Pangolier's positioning and timing (especially if he intends to use Rolling Thunder during combat): 
Vengeful Spirit, 
Keeper of the Light, Huskar, Dark Seer
Dark Seer
* With Normal Punch from Aghanim's Scepter, Dark Seer can gain an advantage against heroes who rely on evasion as Normal Punch has true strike: 
Phantom Assassin, 
Windranger, 
Hoodwink.
Dark Seer
* With Normal Punch from Aghanim's Scepter, Dark Seer can gain an advantage against heroes who rely on evasion as Normal Punch has true strike: Phantom Assassin, Windranger, Hoodwink.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Dark Seer
* Dark Seer can increase the movement speed of allies with Surge, breaking Static Link.
Dazzle
* Heroes that can save their allies can be a big problem for Mars: Dazzle, 
Omniknight.
Dark Seer
* Heroes with hastes: Dark Seer, Lycan
Dark Seer
* Dark Seer relies on Surge for most of his mobility, so he's not very vulnerable to slows, but much more to root effects and walls or pseudo-walls such as Disruptor's Kinetic Field or Slark's Pounce.
Dazzle
* Heroes that can deny Slark early kills will prevent him from snowballing: Dazzle, 
Abaddon.
Dark Seer
* Heroes with AoE abilities will hit Slark in Shadow Dance: Lina, 
Jakiro, Underlord, 
Leshrac, Dark Seer, 
Earthshaker, 
Timbersaw, 
Crystal Maiden.
Dark Seer
* The haste provided by Dark Seer's Surge or a {Rune:Haste} renders Lich's slows ineffective.
Dazzle
* Heroes that can slow Charge of Darkness by a huge amount: 
Venomancer, Viper, Dazzle, 
Arc Warden, Lion, Huskar, 
Shadow Shaman, Visage, 
Undying, Jakiro.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Additional:
* Surge allows for Dark Seer and his allies to escape from Upheaval due to it ignoring any slow.
Dazzle
* Heroes that excel at grouping up with their team very early will be able to take advantage of a Clinkz that tries to pick off heroes that are alone: 
Brewmaster, Dazzle, 
Tidehunter.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Dark Seer
* Heroes who rely on damage over time as Spiked Carapace can block and reflect only one instance of damage: Jakiro, Viper, Venomancer, Huskar, 
Ember Spirit, Dark Seer, 
Sand King, 
Doom, 
Dawnbreaker. However, this also means they are easily stunned.
Dazzle
* Hex abilities can cancel the channelling of Fiend's Grip : Lion, Shadow Shaman, Dazzle from Aghanim's Shard with upgraded Poison Touch.
Dazzle
* Heroes who rely on magical damage resistance may have a hard time laning against Dazzle as all of Dazzle's abilities deal physical damage instead of magical: Anti-Mage, Huskar, Viper.
Dazzle
* Heroes with abilities that can save teammates are also effective such as 
Shadow Demon, Dazzle, 
Oracle, 
Bane, Pugna, Tusk, 
Winter Wyvern, 
Io, Underlord, 
Treant Protector and Keeper of the Light.
Dark Seer
* Heroes with escape abilities: Anti-Mage Dark Seer Slark 
Storm Spirit Windranger Weaver can kite Lifestealer due to him having no lockdown.
Dark Seer
* Heroes that rely on summons will suffer against Ion Shell, which kills them very quickly: Beastmaster, Broodmother, Enigma, Nature's Prophet, Visage, Warlock, Wraith King.
Dazzle
* Support heroes with low mobility can be slowed further by Incapacitating Bite, and swarmed by Spiderlings for an easy kill: Shadow Shaman, Visage, Dazzle, Rubick, 
Lich.
Dark Seer
* Ion Shell zones out Broodmother in the laning phase, and can kill her spiderlings if used on one Spiderling in a group.
* Vacuum can pull Broodmother out of the treeline.
Additional:
* Ion Shell is a very powerful weapon against Broodmother's Spiderlings and makes her laning much harder.
Dazzle
* Some heroes with extreme range, like Zeus, Invoker or Clockwerk, can snipe your allies from anywhere after your Grave has expired.
Dazzle
* Aghanim's Shard upgraded Poison Touch can be used to hex Clockwerk, silencing him, disarming him, slowing him, and muting him, and thus rendering him unable to use 
Blade Mail to return damage or to do anything at all.
* Shadow Wave will hit Clockwerk every time when he's fighting with an enemy inside Power Cogs.
* Due to Clockwerk's very low damage output, Dazzle will have more than enough time to Shallow Grave any enemy hero Clockwerk initiates on.
Additional:
* Shadow Wave will hit Clockwerk every time when he's fighting with an enemy inside 
Power Cogs.
* Due to Clockwerk's steady damage output, Dazzle has plenty of time to Shallow Grave anyone Clockwerk initiates on.
Dazzle
* Dazzle's lack of a true disable makes him a relatively vulnerable target for Phantom Assassin.
* Coup de Grace will often kill Dazzle's teammates before he has a chance to use Shallow Grave.
Dazzle
* Hex abilities prevent attacking, ability and item usage, which is a severe problem for Phantom Assassin as it prevents her from using Black King Bar, the one item that helps protect her against the aforementioned dangers. Doom and Shadow Demon with Aghanim's Scepter also disables Phantom Assassin's Evasion and Critical Strike, removing much of her damage and survivabaility: Doom, Disruptor with Aghanim's Scepter, Dazzle with Aghanim's Shard
Dark Seer
* With Normal Punch from Aghanim's Scepter, Dark Seer can gain an advantage against heroes who rely on evasion as Normal Punch has true strike: Phantom Assassin, Windranger, Hoodwink.
Dark Seer
* Heroes without blink mechanisms or spell immunity will have a hard time positioning against 
Pit of Malice: 
Sven, 
Tiny, Wraith King, 
Dragon Knight, 
Meepo, Doom, 
Bounty Hunter, Dark Seer, Undying, 
Alchemist, Legion Commander.
Dark Seer
* Heroes with strong area-of-effect damaging and/or disabling abilities will be able to intercept Underlord and his team when they exit from Fiend's Gate: 
Luna's Aghanim's Scepter upgraded 
Eclipse, Dawnbreaker's 
Solar Guardian, 
Axe's 
Berserker's Call, 
Mars's 
Arena of Blood, Jakiro's 
Macropyre, 
Dual Breath and 
Ice Path, Naga Siren's Song of the Siren, 
Razor's 
Eye of the Storm and 
Plasma Field, Lina's 
Light Strike Array, Broodmother's 
Spinner's Snare from Aghanim's Scepter, 
Elder Titan's 
Earth Splitter and 
Echo Stomp, Alchemist's 
Unstable Concoction and 
Acid Spray, Queen of Pain's 
Sonic Wave, Dark Seer's Wall of Replica and Vacuum, Venomancer's 
Noxious Plague and 
Poison Nova from Aghanim's Scepter, Oracle's Fortune's End and 
Rain of Destiny from Aghanim's Shard, Bloodseeker's Blood Rite, Enigma's 
Black Hole and 
Midnight Pulse, 
Shadow Fiend's 
Requiem of Souls, 
Batrider's Aghanim's Scepter upgraded 
Flaming Lasso, 
Firefly, 
Flamebreak and 
Sticky Napalm, 
Ancient Apparition's Ice Blast, Sand King's 
Epicenter, 
Sand Storm and 
Burrowstrike, Gyrocopter's 
Call Down, Ember Spirit's 
Sleight of Fist, 
Death Prophet's 
Exorcism and 
Silence, 
Monkey King's 
Wukong's Command, Crystal Maiden's 
Freezing Field, 
Muerta's 
The Calling, 
Medusa's 
Stone Gaze, Zeus's 
Nimbus from Aghanim's Scepter. 
Dark Willow's 
Bramble Maze, 
Pangolier's 
Swashbuckle, 
Grimstroke's 
Soulbind, 
Ink Swell and 
Stroke of Fate, Earthshaker's 
Echo Slam and 
Fissure, 
Puck's 
Dream Coil and 
Waning Rift, Winter Wyvern's 
Winter's Curse, 
Magnus's 
Reverse Polarity.
Dazzle
* Spectre's entire ability set is designed to get to and destroy heroes that stay in the backlines, both carries (like the aforementioned 
Drow Ranger and 
Sniper) and supports (like Dazzle and Shadow Shaman).
Dark Seer
* Dark Seer can pull together Spectre's illusions with Vacuum, and Wall of Replica creates an illusion of Spectre that deals massive damage.
Dazzle
* Although
Counterspell's passive component doesn't protect Anti-Mage from the physical damage nukes from Poison Touch and Shadow Wave, a well-timed use of it will reflect Poison Touch back to Dazzle, slowing him in the process.
Aghanim's Shard, as 
Counterspell will reflect the hex back to Dazzle.
Mana Break drains mana, which can be a problem for Dazzle, as all of his abilities have a high mana cost. This makes him especially vulnerable to 
Mana Void.
* This can be even more dangerous if Dazzle has an
*
Dark Seer
* Dark Seer's strength lies in his high-mana cost skills. So
Mana Break can be a great nuisance for him, since it can reduce his mana and prevent him from casting his spells.
Mana Void can deal a lot of damage if Dark Seer spent a lot of mana on his abilities.
*
Dazzle
* Heroes who rely on magical damage resistance may have a hard time laning against Dazzle as all of Dazzle's abilities deal physical damage instead of magical:
Anti-Mage, 
Huskar, 
Viper.