Let me show you why Sven is called "Rogue" Knight (6.81b)
By Obama Bin Laden
Sven is a melee strength hero with huge potentials. He can both go initiator, tank, disabler, carry, support. Besides that, he can also go "Rogue", which is my favorite part.
With this way, you'll be the best initiator in the game and also will be guaranteed to win the teamfight (unless you have a really noob team), since no hero in the game can have that much cleave and damage at the same time.
What you're supposed to do is when you are about to barge in a gank or sneak attack a farmer, use this combo:
Soul Ring+Mask of Madness+God's strength+Shadow Blade and Storm Bolt+BKB(Situational) right after going out of invisibility. You can kill even the most dodgy escape heroes(like puck or antimage) in the blink of an eye.
Your teammates will tell you to be a classic punching bag Sven, wanting you to pull out a bkb or ac as soon as possible. DO NOT LISTEN TO THEM. This is not Sven is supposed to be. Don't forget that: You are a ROGUE, not a PALADIN.