Viper DPS/Carry

Intro

* Any Lane
* Carry/DPS

Utilising Viper's poison ability:
@Start: Harass
@Early: Harass, and possible early kill (Generally works well with a stun from a team mate)
@Mid: DPS
@Late: Tank

Viper's Poison Attack (Q), has an effective slow effect, along with the slow effect of venom orb it can be a very big game changer.

Detailed

Start

This build requires you to get the last hits on creeps quite often. This is why the Quelling Blade is chosen from the start, as it gives you the extra 12% range bonus on creeps and can make it easier to gain that last hit, and works well with the Nethertoxin passive ability.

Generally the Tango is only needed if an enemy is harassing you back and to keep you in the action.

Once you have your Posion Attack start harassing the enemy hero(s) just to push them away from battle and keep their health a bit lower so they think twice about going for you.

After you've gained enough to purchase the Orb of Venom from the secret shop, I'd recommend picking it up, just to add that extra bit of damage, and the slow effect will come in handy if you wish to work with a team mate to grab an early kill and some extra coin.

You will also want to pick up those Power Treads soon after as well just to give you the little bit of movement speed, and attack speed to both evade enemy heroes and begin your DPS increasing.

Mid Game

Mid game is when most players have worked their heroes enough to begin doing some damage, and there is nothing worse than running out of mana from using your Posion Attack, and either running back to base for health, or waiting ages just to battle again, so the Perseverance ring helps keep you in the battle and keep up the harassment which gives your team the opportunity to pull off a successful gank.

Next the Yasha will give you the added attack speed and damage along with a little bit more movement speed just to keep your upper edge.

Once you've earned up the coins again, make sure you purchase the Ultimate Orb, as the attribute bonus is very handy, and you are almost complete with the Manta Style.

Note: Remember to keep on the move, harass, and watch out for enemy ganks on your location, as you may be powerful in a 1vs1 situation, but you still won't have that power to take on several decent players at once.

Late Game

First you will want to complete the Manta Style from this point you are pretty much set, but it is a good idea to grab yourself a hyperstone, as it will allow viper to chop through creeps, and apply the slow effects of his attacks much faster.

Now the coins will be racking in by the second, and when using AUTOCAST for the Poison Attack against enemy heroes you can watch their health rapidly deplete.

Luxury

Generally following this guide you should attain enough coins to purchase luxury items, and level up Viper pretty quickly, though when it comes to purchasing Luxury items I can recommend following the order Butterfly->Ethereal Blade->Monkey King Bar

Additional Notes

1) Aim to get last hits on creeps constantly.
2) Harass Enemy heroes at the start to make them think twice about ganking.
3) If you are on about 1/3 health early game and mid game, then hold back a bit to gain health, you don't want the enemy to kill you.
4) Make good use of your Ultimate, then Autocast Poison Attack for enemy heroes to really lay down the damage.

ALSO: If you are unable gain the last hits on creeps, you may want to try a different guide.

Team Work

Obviously you will need to co-ordinate with your team, but with this build Vipers ability to slow enemies is important to help your team catch those faster heroes who are making a good run for it.

If you find yourself being ganked, do the hurt on the ranged heroes as Viper will take them down fairly quickly, and the Close-combat heroes will receive damage from your Nethertoxin skin, once the range are gone then you may be able to make an escape.

If possible try to work with a support class who can use stuns, or even a fast moving close-combat hero, as the slow effect from attacks makes it easier to cast stuns, or to catch up and deal some major hurting.

Try to move between top and bottom, providing support in the middle as you go, as you will be able to help your team catch enemies off guard and polish them off easily.