Ryze in a nutshell:
Runes: CD reduction, Magic pen, Flat health and can either do AP or HP per level
Build order: Spell flux, overload, rune prison, then focus on maxing out overload 1st and rune prison last.
Summoner spells ill usually take ghost and clarity
Item build: Sorc boots, Archangels x3 Zhonyas ring and void staff
Start off with the mana gem 1st and work up to the tear then focus on boots, When you have the boots finish off the archangels, get a void staff then 1 more archangels, zhonyas and another archangels
With this build you will be squishy but you will 1 combo to death most champs. Ability Rotation should be R, E, W, A R first due to the increase AP, E next for the magic pen, then snare and finish off with overload. If this doesnt kill them it will be **** near close and spell flux should be available again to finish them off.
Check out Leaguecraft.com they have some updated guides