Viper

Viper is a ranged Carry hero who can also function as an excellent ganker due to his slowing auto-attacks and his ultimate. Although ganking is often made easier with Viper's presence, it's often times that sheer item power could reveal Viper true carry potential. Farming with Viper is relatively easy, however, active participation in ganking is very important before the ganking power wears out (when enemy heroes become more aware / careful as well as their items become better). Thus, Viper is recommended for at least intermediate to decent players as ganking does require good game sense, awareness and reflexes. Orb-walking with Poison Attack also makes Viper very potent in hero harassing and pushing. In the hand of a pro player, Viper can be very deadly.