This is my first guide on this site so any and all feedback is appreciated.

That being said I build Lissandra with a bit of tankiness, I believe this is the way she was meant to be played. You will notice a prefer a strong early game setup over scaling runes and such. I play Lissandra almost as a support rather than a Mage. She is very powerful at disrupting fights and picking people off. I have a lot of fun playing Lissandra this way and encourage you to try this build.

I do not believe in scaling runes for the most part. I would take the bonus in early laning to snowball ahead any day. So glyph of Ability Power and mark of Magic Penetration is the way I go. I do use scaling HP seals because 50ish HP at the start isn't much.

In most cases I get all three of the HP/AP combo items for Lissandra. I prefer a very sustainable Lissandra to help initiate and disrupt fights. But of course every game is different. I recommend getting defensive items before you try building a pure offense Lissandra.

I get Glacial Path at level 2 over Ring of Frost to help escape early jungle ganks, or if I get myself in a sticky situation. Ring of Frost does not give any real benefit at level 2, so save it for level 4.

+Great burst damage
+Very elusive/invasive
+One of the tackiest mages
+Amazing in team fights
+Versatile ultimate

-very very slow
-easy to get "too" invasive
-long base cooldowns