Hello and welcome, this is my very general guide to Kassadin, The Void Walker. Kass is a caster assassin, next to Leblanc, he is currently the only one in the game. My Kassadin build is based for going into a fight, unloading everything, get out safely, and if needed go back in.

My runes allow me to have mana always on the go and continue to spam Force Pulse in team fights. Other then the health quint to keep me alive early game, its a standard caster build.

I go 9/21/0 to ensure my defences are locked up. Kass is normally focused so this allows it to be a struggle to focus him while doing tons of damage.

Tear, Sheen and RotA are MANDATORY!! These allow you to have a large mana pool, a strong melee attack to go with your W, and a beefy health pool for a caster, let alone a assassin.

I max out my Q right away, as team fights don't occur early game, so your E wont be much use. I get a point in W at lvl 5 to help with mana a tad bit, and to help build tear mana stacks and proc sheen when possible.

Ignite is awesome for enemies getting to far away with no health, also it helps early game a lot.
Cleanse allows me a free R, normally the trick to kill Kass is to CC him to death, with Cleanse that isn't the case. Why no flash? Why would you? Kass has a 6 second at most CD on a flash, why need another that you cannot use if you are CC'd? Cleanse allows free R's and get away safely.

Overall, if you try this build you should see some spectacular results, feel free to look at my profile, out of 3 ranked games I have only died once and have gotten many kills/assists. Thank you for reading my guide on my main Dps Champ, Kassadin.