Viper Overview

Lore & Bio

"You've failed the acid test."

In the deep dark caverns of the Nether Reaches, there is a race of flying reptiles ,which is called Netherdrakes, and has been living there for several eras since the tectonic shift happened and trapped them inside. This race is famous for their powerful poison and acids that can melt away any metals. And among the race, Viper is the well known Netherdrake as his desire for dark magics. Although the door to the outside world was closed millions of years ago, he somehow managed to free himself and get out of the Nether Reaches. By then, this deadly creature was captured by the elderly mage who wanted to tame and kept him as a pet. 

As the craving for magic was so strong, Viper obeyed and succumbed to the master in order to learn the spells. But soon, he was fully aware of how powerful his toxins are, comparing to the few spells. The acid drooling from Viper quickly melted down the metal cages, he sprung out of the control of his master, spitted the poison right in the eye of the old spellcaster and flew away as a sign to the world that he had a new master.

In-game, Viper is described as: 

“Launching deadly poison from a distance, Viper poses a grave threat to whomever he targets. As his various toxins eat away at an enemy's health and slow their movement, Viper simply does what he does best: he keeps adding more poison.”

Attribute & Stats

• Strength: 21 + 2.4 each level;

• Agility: 21 + 2.5 each level;

• Intelligence: 17 + 2 each level;

• Health: 620;

• Health regeneration: + 2.1 each second;

• Mana: 279;

• Mana regeneration: + 0.85 each second;

• Damage: 48 - 50;

• Amor: 1.5;

• Magic Resistance: 25%;

• Turn Rate: 0.6;

• Attack Range: 575;

• Projectile speed: 1200;

• Attack Animation: 0.33+1;

• Movement: 275;

• Sight Range: 1800/800;

• Base Attack time: 1.7 seconds per attack;

• Damage Block: 0;

• Collision size: 24.

Abilities & Talents

Notes:

The attack range granted by talents affects the Poison Attack’s cast range.

The spell lifesteal granted by talents can stack up with other spell lifesteal.

• Non-heroes units and creep-heroes will be healed for 1.6%. Does not heal off illusions.

The health granted by talents expands the health pool and the current health will remain.

The attack damage granted by talents is raw attack damage.

• Illusions don't get this bonus damage. Furthermore, most percentage-based damage increasing or reducing effects don’t affect bonus damage from talents.

Skills building guide

In this build I will focus on guiding you how to play Viper in the mid lane. For level 1, we should add one point in Nethertoxin as It is useful to clear the creeps quickly and to harass if the opponent is a melee hero. Then the first ability I recommend you max out is Poison Attack as it increases both magical and physical damage amount.Besides, the slow effect can be useful while chasing the enemy. Also, in the laning phase, you can easily harass the enemy heroes.

The second ability to max out is Corrosive Skin due to the magical resistance it grants and the DPS damage and slow debuff it can cause. Nethertoxin is your last priority. Although this ability is great and useful due to the AoE and DPS damage it can cause, it is really easy to dodge and get out so you should place only one point on this skill in the early game.

Abilities

Poison Attack

Poison Attack (Unit Target, Magical)

Effect: Viper breathes out the toxic toward the target which causes damage per second, slows the enemy and reduces magic resistance. The attack can be stacked up to 5 times.

Mana cost: 20/22/24/26

Cooldown: 0

Max Stacks: 5

Range: 600/640/680/720 (Talents: 700/740/780/820)

Damage per Second per Stack: 4/8/12/16

Move Speed Slow per Stack: 6%/8%/10%/12%

Magic Resistance Reduction per Stack: 3%/5%/7%/9%

Duration: 4

Upgradable by Aghanim’s Shard:

• Armor Reduction per Stack: 1
• Building Damage Percentage: 40%
• Max Stacks: 8

Notes:

Undispellable

The cast range of Poison Attack depends on the Viper’s attack range.

• When the attack range of Viper increases, the cast range increases too. However, the cast range of Poison Attack won’t be changed by cast range bonuses.
• The talent bonus can increase the cast range to 700/740/780/820.
• No matter whether Poison Attack is casted automatically or manually, it still depends on the Viper’s present attack range.

When the targets get hit, they receive the debuff and the following attacks also stack.

• The amount of stacks can be seen by everyone on the map.
• The total stack duration will be refreshed every new attack the target receives.

The detail of movement speed and magic resistance reduction which is caused by Poison Attack with the number of stacks on each level:

• Level 1: 6%/12%/18%/24%/30%/36%/42%/48% movement speed and 3%/6%/9%/12%/15%/18%/21%/24% magic resistance.
• Level 2: 8%/16%/24%/32%/40%/48%/56%/64% movement speed and 5%/10%/15%/20%/25%/30%/35%/40% magic resistance.
• Level 3: 10%/20%/30%/40%/50%/60%/70%/80% movement speed and 7%/14%/21%/28%/35%/42%/49%/56% magic resistance.
• Level 4: 12%/24%/36%/48%/60%/72%/84%/96% movement speed and 9%/18%/27%/36%/45%/54%/63%/72% magic resistance.

Each Poison Attack deals damage every 1 second right after the debuff is applied which means there will be 4 damage instances in total

The detail of damage per second and total damage which Poison Attack deals with the number of stacks on each level:

• Level 1: 4/8/12/16/20/24/28/32 damage per second and 16/32/48/64/80/96/112/128 total damage.
• Level 2: 8/16/24/32/40/48/56/64 damage per second and 32/64/96/128/160/192/224/256 total damage.
• Level 3: 12/24/36/48/60/72/84/96 damage per second and 48/96/144/192/240/288/336/384 total damage.
• Level 4: 16/32/48/64/80/96/112/128 damage per second and 64/128/192/256/320/384/448/512 total damage.

The debuffs will be applied first on the target then the damage.

Poison Attack affects enemy units only, does not affect allied units and wards.

With the upgrade from Aghanim’s Shard, Poison Attack can apply damage and debuffs on buildings.

• The amount of armor reduction is 1/2/3/4/5/6/7/8 per stack.
• The percentage of magic resistance reduction is 24%/40%/56%/72% when the stack is full.
• According to the percentage of magic resistance reduction above, the total damage that this spell can deal on the buildings is 63.49/143.36/239.62/352.26.

Nethertoxin

Nethertoxin (AreaTarget, Magical)

Effect: Viper splits out the poison at the targeted area causing damage to the enemy units in that area. The longer they stay in the affected area, the more damage they receive. Besides, all the passives of the units will be disbaled while they are in this area.

Cooldown: 14 (Talents: 3)

Cast Animation: 0.2+0.5

Cast Range: 900

Mana Cost: 85

Radius: 400

Min Damage per Second: 15/20/25/30

Max Damage per Second: 80/100/120/140

Max Damage Duration: 4

Damage Interval: 0.5

Aura Linger Duration: 0.5

Duration: 8

Notes:

Undispellable

The flying speed of Nethertoxin’s projectile is 2000.

The debuffs and damage of Nethertoxin are provided in the form of aura.The debuff will last for 0.5 seconds.

Nethertoxin deals damage every 0.5 second right after the debuff is applied which means there will be 17 instances in total.

Each 0.5 seconds the enemies spending in the affected area, they will receive damage by 4.06/5/5.94/6.88, which means the damage the enemies receive per instance:

• Level 1:7.5 / 11.6 / 15.6 / 19.7 / 23.8 / 27.8 / 31.9 / 35.9 / 40 / 40 / 40 / 40 / 40 / 40 / 40 / 40
• Level 2: 10 / 15 / 20 / 25 / 30 / 35 / 40 / 45 / 50 / 50 / 50 / 50 / 50 / 50 / 50 / 50
• Level 3: 12.5 / 18.4 / 24.4 / 30.3 / 36.3 / 42.2 / 48.1 / 54.1 / 60 / 60 / 60 / 60 / 60 / 60 / 60 / 60
• Level 4: 15 / 21.9 / 28.8 / 35.6 / 42.5 / 49.4 / 56.3 / 63.1 / 70 / 70 / 70 / 70 / 70 / 70 / 70 / 70

If the enemies standing in the affected area for the whole spell duration, the damage they receive is 533.75/670/806.25/942.5 damage.

Whenever the enemies leave the area, the damage value will be reset. If they re-enter the area, it will count again.

Nethertoxin’s debuffs do not stack with multiple instances.

The damage affected units do not increase accordingly when this ability is leveled up.

• If the debuffs are applied after this spell is leveled up, the ;latest damage values will be applied too.

Corrosive Skin

Corrosive Skin (Passive, Magical)

Effect: Viper oozes the contagious toxin to cover his body that deals damage and reduces the attack speed of anyone attacking him. Besides, Corrosive Skin also increases his magic resistance.

Max Proc Distance: 1400

Magic Resistance Bonus: 10%/15%/20%/25% (Talents: 20%/30%/40%/50%)

Damage per Second: 8/16/24/32

Attack Speed Slow: 8/16/24/32 (Talents 16/32/48/64)

Duration: 4

Notes:

Magic resistance bonuses from Corrosive Skin can be stacked with other sources of magic resistance which are granted by items or allied units.

The total percentage of magic resistance Viper receives after using Corrosive Skin is 33%/36%/40%/44% (Talents 40%/48%/55%/63%).

If the attacking units are within 1400 range, they will receive damage and reduce in movement speed.

Corrosive Skin is the spell that has the no-reflection flag which means the damage it deals can not interact with other no-reflection flag damage.

• Any damage is flagged HP Removal does not react with Corrosive Skin.
• If the damage is dealt by the other things not by the caster (e.g: Proximity Mine, Death Ward). The Corrosive Skin is not triggered and does not affect the caster.

Corrosive Skin deals damage every 1 second right after the debuff is applied which means there will be 4 damage instances in total.

The total amount of damage that spell can cause is 32/64/96/128 damage (before reductions).

The procs of Corrosive Skin does not stack even when the same enemies attack Viper consecutively, but the debuff duration is refreshed.

Buildings, wards, invulnerable and allied units won’t be damaged or debuffed by Corrosive Skin.

Viper Strike

Viper Strike (Unit Target, Magical)

Effect: Viper flaps his gruesome wings towards and releases two glowing projectiles that reduces the target movement and attack speed while dealing the damage per second. The slowing effect fades away over time and ends at the same time with the poison effect.

Cast Animation: 0.3+ 0.53

Mana cost: 100/150/200

Cooldown: 50/40/30

Cast Range: 500

Damage per Second: 80/120/160 (Talents: 160/200/240)

Move Speed Slow: 40%/60%/80%

Attack Speed Slow: 40/60/80

Duration: 5

Upgradable by Aghanim’s Scepter:

• Cast Range: 900
• Mana cost: 125
• Cooldown: 10

Notes:

The flying speed of Viper Strike is 1200.

The slow will fade away which means the movement and attack speed of the targeted units will be recovered by 0.3%/0.4%/0.5% and 0.267/0.4/0.533 respectively.

If using Viper Strike on the same target many times, its effects do not stack but the debuff duration is refreshed.

The particle effect on Viper’s wings works as a visible indication for everyone that this spell is being cast.

Effective items guides

Early game

Enchanted Mango

Enchanted Mango grants Viper a large amount of mana which helps him cast the spells more frequently.

Tango

Tango keeps Viper in lane longer.

Faerie Fire

Faerie Fire grants a small amount of damage and instant heal, which helps Viperto last hit the creep.A reliable source of HP restore.

Iron Branch

Iron Branch: a great combination with Tango in terms of healing.

Mid game

Magic Wand

Magic Wand instantly restores mana and health which helps Viper to cast more Poison Attack.

Wraith Band

Wraith Band: increase damage and durability due to the base stats bonuses.

Infused Raindrops

Infused Raindrops: grants mana regeneration and magical damage block.

Boots of Speed

Boots of Speed: increases mobility.

Arcane Boots

Arcane Boots expands the mana capacity and is a great source of instant mana restoration which helps Viper to cast his spells more often.

Rod of Atos

Rod of Atos: a powerful tool for ganking by rooting the enemies or catching the split-pushing hero besides the stats bonuses.

Late game

Guardian Greaves

Guardian Greaves is upgraded from Arcane Boost. Useful item in the combat when restoring a quite decent amount of mana and health for all allies and even removes most debuffs.

Aghanim's Scepter

Aghanim’s Scepter: Reduce the ultimate’s cooldown and mana cost which means Viper can cast Viper Strike more freely.

Situation items

Veil of Discord

Veil of Discord: amplifies the magical damage caused by Viper’s abilities and grants attributes and armor.

Shadow Blade

Shadow Blade: with Shadow Walk, Viper can sneak into the great position to deal damage or to gank before the enemy could recognize.

Heaven's Halberd

Heaven’s Halberd grants great bonuses as well as a hard counter for any physical damage heroes. Besides, Halberd can prevent a target from attacking for a certain amount of seconds.

Sange and Yasha

Sange and Yasha: a great item for the mid game, Viper can take advantage of the additional health, damage and movement speed.

Black King Bar

Black King Bar grants Viper with Spell immunity.

Monkey King Bar

Monkey King Bar: grants decent magical damage, piercing damage and a little attack speed.

Nullifier

Nullifier: More damage,armor and health regeneration for Viper. It is also a great item to guard Viper against mobility items like Blink Dagger or Force Staff or disable items like Orchid Malevolence and Scythe of Vyse. It can even be used to counter BKB and Glimmer Cape.

Manta Style

Manta Style: creates an illusion which can cause bonus damage or distract the enemy while escaping as well as grants decent attributes.

Mjollnir

Mjollnir: synergizes well with other Viper’s DPS abilities as well as grants a great amount of attack speed to enhance Poison Attack.

Heart of Tarrasque

Heart of Tarrasque: A total 1300 health and 14.5 health regeneration are what Viper receives when buying this item. Viper can survive longer in a teamfight.

Eye of Skadi

Eye of Skadi grants Viper great bonus stats and its activation instantly weakens the enemy hero.

Bloodthorn

Bloodthorn silences the enemies and increases Viper’s damage output preventing them from fightback or runaway.

Octarine Core

Octarine Core: increase the magical damage output of Viper by reducing the cooldown and increasing mana pool, regen and cast range.

Radiance

Radiance synergizes well with Viper abilities as its activation causes DPS damage.Might consider purchasing this item when already having Heart of Tarrasque or Manta Style.

Enemies & Allies

Allies

Abaddon

Aphotic Shield and Mist Coil can heal Viper and absorb the damage he receives which makes Viper nearly invincible. Besides, Curse of Avernus synergizes with the Poison Attack quite well.

Beastmaster

Beastmaster: The attack speed boost from Inner Beast  can increase the DPS when Viper casting Poison Attack. Primal Roar’s disables can help Viper deal more damage.

Clockwerk

Clockwerk: Precise Hook Shot and Power Cogs can trap the enemy inside which is the perfect setup for Viper to cast Poison Attack and Viper Strike.

Crystal Maiden

Crystal Maiden: With Arcane Aura, Viper can have more mana regeneration which helps him cast more Poison Attack. Viper can distract enemy heroes by harassing them so Crystal Maiden can have enough time to channel Freezing Field.

Dark Seer

Dark Seer: Ion Shell synergizes well with Viper’s abilities which can deal tons of DPS. Surge allows Viper to reach his maximum speed that helps him kite the melee heroes easily or dodge other spells.

Dazzle

Dazzle: Poison Touch works well with Poison Attack as both abilities do deal DPS and slow debuff. Shadow Grave and Shadow Wave can save Viper from being killed by burst out damage or work as a lifebuoy so Viper can continue to cause more damage. Besides, Bad Suju reduces the armor on the enemy which makes Viper’s attack deal more damage.

Drow Ranger

Drow Ranger: the great attack speed granted by Precision Aura makes Viper difficult to handle in his laning phase. There is nearly no chance for the enemy to run away when Drow Ranger casts Gust and Frost Arrow in combination with Viper’s slow debuff abilities. Corrosive Skin allows Viper to tank while Drow Ranger deals damage in the back line.

Earth Spirit

Earth Spirit: With the perfect set-up from Earth Spirits by casting Boulder Smash, Rolling Boulder and Geomagnetic Grip, Viper can freely deal damage and both can roam around the match to seize the vision and gank the enemies. Magnetize combined with Nethertoxin and Poison Attack can deal tons of damage on the targets in the affected area

Faceless Void

Faceless Void: Chronosphere confines enemies in an orb so Viper can pick off easily. With the help from Time Dilation by extending enemy cooldowns, Viper can easily deal with some troublemakers.

Lich

Lich: Frost Shield protects Viper from receiving too much damage as well as counters gank by slowing the nearby enemies.Sinister Gaze can secure the kill for Viper when the prey tries to run away.Chain Frost can guard Viper against being dogpiled by the enemies in the combat. Without the help and distraction from Viper, Lich can’t cast his abilities in the teamfight due to his lack of mobility.

Luna

Luna: Lunar Blessing grants Viper attack speed and vision range which increases Viper’s damage output and gives him a leg up in the nighttime. Besides, Viper can make space for Luna to farm to get the expensive items as soon as possible. 

Necrophos

Necrophos: Heartstopper Aura drains down the enemy's health steadily, making them a great prey for Viper to cast Poison Attack. Viper can take advantage of the small amount of health healed by Death Pulse. Besides, Necrophos’s common items also synergize well with Viper’s abilities such as Radiance, Veil of Discord and Guardian Greaves.

Ogre Magi

Ogre Magi: Viper farms quicklier when Orge Magi incite frenzy in him by casting Bloodlust. In the early game, Viper can make enough space for Viper to farm due to his Ignite and high base attribute.

Slardar

Slardar: Slithereen Crush disables the channelling abilities and stun the enemy so Viper can have a sure kill. By reducing armor on the target, Corrosive Haze can increase the damage caused on the enemy by Viper.

Treant Protector

Treant Protector heals and provides armor for Viper by casting Living Armor. Overgrowth roots the enemies down so Viper can free throw the Poison Attack. 

Counters

Broodmother

Broodmother: Due to Viper's lack of mobility and escape, he is easily harassed by the creeps created by Spawn Spiderlings.With Insatiable Hunger, Broodmother can win the duel with Viper but still keep his health in the safe state.

Chaos Knight

Chaos Knight: Just in the blink of an eye, Viper is stunned and drawn close to Chaos Knight when he casts Chaos Bolt and Reality Rift respectively which leave Viper no room to react. The high damage output from Phantasm and Chaos Strike can grant Viper an instant death.

Invoker

Invoker: Ice Wall and Ghost Walk are tools for Invoker to kite Viper or slow him down when escaping. Chaos Meteor and Sun Strike can kill Viper quickly due to the high damage they can deal. Cold Snap, Tornado and Deafening Blast disables Viper from casting spells and dealing DPS. EMP constrains the amount of spells Viper can cast due to the mana burning debuff. Forge Spirit melting Viper’s armor which makes him more vulnerable in the combat or teamfight.

Morphling

Morphling can run away or escape from Viper by casting Wave Form. The huge amount of health Morphling attains when casting Attribute Shift (Strength Gain) make Viper’s DPS hardly affected. Morphling can morph into Viper and use his own ability against him.

Lifestealer

Lifestealer: Viper Strike deals zero damage on Lifestealer when he casts Rage. However, the slow and spell immunity pierce debuffs still affect Lifestealer. Feast and Open Wound can help Lifestealer survive the DPS from Viper when dueling.

Phantom Lancer

Phantom Lancer: with many illusions created by Spirit Lance and Doppelganger, Viper is confused and hard to handle because his skills mostly are single target (except Nethertoxin). The slow debuff from Viper is totally useless when Phantom Lancer casts Phantom Rush to approach him.

Pugna

Pugna instantly disarms Viper and interrupts his DPS by casting Decrepify. Nether Ward forces Viper to be more prudent when casting spells as the more spells he casts the larger the damage he receives. As having no tool to disable the channeling ability so Viper can not resist when Pugna uses Life Drain. 

Rubick

Rubick is notorious for stealing opponent’s abilities so Viper will have a hard time dueling with him. As Nethertoxin can disable the passive so Rubick steals it by casting Spell Steal and uses it to deactivate the Corrosive Skin of Viper. He can also steal Viper Strike to weaken the main carry in combat.

Terrorblade

Terrorblade: swaps HP with Viper by casting Sunder can turn the table around and put Viper in the dangerous situation. Viper will be vaporized quickly when Terrorblade is under Metamorphosis.

Weaver

Weaver: With the help from Shukuchi, Viper can’t slow Weaver. Time Lapse will make all the DPS caused by Viper become useless and undoes poison damage.

Windranger

WindRanger: When Winrun is activating, the projectile from Viper can not cause damage and debuff on Windranger. With low mobility, Viper struggles from dodging Shackleshot and Powershot. A large amount of damage can be dealt with in a short period of time by Focus Fire can put Viper in the low HP state more frequently.

Wraith King

Wraith King: Viper can’t stand the high burst damage from Wraith King.

Items Counter

Town Portal Scroll

Town Portal Scroll: As Viper has no tool to disrupt channeling abilities so he can’t prevent a healthy opponent from teleporting.

Black King Bar

Black King Bar: most Viper’s abilities become useless.

Blink Dagger

Blink Dagger: can easily get away from Viper as he can not follow the opponent due to the low mobility.

Ghost Scepter

Ghost Scepter and Ethereal Blade make Viper’s attack less effective.

Glimmer Cape

Glimmer Cape prevents Viper from attacking the owner and reduces received damage by granting magic resistance.

Force Staff

Force Staff: the owner can easily increase the distance and escape from Viper

Silver Edge

Silver Edge disables Viper’s passives and reduces his durability

Manta Style

Manta Style confuses Viper and lets him waste his resources by creating 2 illusions.

Diffusal Blade

Diffusal Blade slows Viper down and burns his mana which makes him more fragile and hard to cast spells.

Linken's Sphere

Linken’s Sphere: Its activation disables Viper completely from dealing damage.

Lotus Orb

Lotus Orb reflects the damage and debuffs towards Viper.

Favorable Matchups

Game plan

Early game

Farming,farming and farming are Viper priority in the early game. Use Nethertoxin to weaken the creeps,Poison attack to last hit the creep, harass the enemies and prevent them from farming. If you are dueling with a mobility hero in your lane, try to hold your position to farm and wait for the jungle or supporter to help you secure the skill. When clearing the creep wave, you can start to roam to another lane to gank if you see the sign of that in the mini map.

Mid game

Your priority is still farming but be ready to engage in any imminent fights.Due to the low mobility you should start to move when you sense where the fight can happen and be one leg ahead. Make sure you only do that when clearing up the creep waves in your lane or winning your lane. Immediately go back to your lane when finishing the gank to maximize the efficiency and destroy the wards on your way back to the lane if possible.

Late game

Your objectives in the late game are quite the same with the mid game but this time you and your team might play around the keys objectives like Roshan and towers. As you are a great source of DPS so finding a good position to cast spells is a must. The longer you stay in the teamfight the more damage you are going to deal. And remember any winning teamfight in the late game can lead to the victory in the end.