Viper is a ranged agility hero that is typically played in the mid lane or on the offlane. He is notable for being an anti-carry hero, and excels at crippling carries that lack mobility and/or attack range.
Skills
All of his abilities are viable so there's no strict build order.
If playing aggressively prioritise maxing Poison Attack, followed by Nether Toxin to increase your killing potential.
If being heavily harassed in the lane feel free to prioritise Corrosive Skin and adopt a more defensive build order.
Always get Viper Strike (levels 6, 11 and 16).
Items
Starting Items: A set of Tangos, Healing Salve, Circlet, 3x Iron Branches.
Early Items: Boots of Speed into Power Treads, Magic Wand, Wraith Band into Ring of Aquila.
Core Options: Mekanism (ideal) or Shadow Blade (pub-stomp) then Aghanim's Scepter.
Luxury Extensions: Crimson Guard, Manta Style, Assault Cuirass, Black King Bar, Heaven's Halberd, Orchid, Butterfly, Monkey King Bar.
Situational Items: Courier and/or Observer Wards (if no one else buys), Drums of Endurance, Pipe of Insight.
