Thanks for comment man. To be honest i actually dont have a rune page for my Mages as yet. So i just sort of made that up a bit. With the mana issue early game, it is a problem and could be combatted with runes and such. Thats why i chose teleport as a spell. Teleport can refuel your mana pool quickly and u can get right back to the fight.
Also with masteries thats just a quick rough guide i came up with. Still needs some tweaking. And depending on the situation in the late game really depends on what your sixth item should be aswell. If theres alot of magic resistance then definitely go with void staff. Its really dependant on the situation to what to buy last. But those 5 items in that order i believe is your greatest build.

Interesting build and good advice, particularly for early game. Everybody should remember that playing safe is the key of a good early game, whatever the champ (of course if you have a soraka or a taric with you on the lane, you can play a more agressive thanks to heals).

"More often than not Ryze will pick up the kill in a gank because he dishes out the most splash damage. And if not he will get an assist which will add to his Soulstealer stacks."
This is also a really good point. Too many people want to kill (and often die because of that). The role of a Ryze in a team fight is to make huge AOE damages at the beginning of the fight. Stay out of the clash and spam your skills on CD.

"I would probably not choose Void Staff as the runes already offer a fair bit of Magic Penetration."
You have only 13 MP on tour runes, a single banshee is 57 MR. I think the Void is worth the price, particularly if opponents stack MR because you make heavy damages.

Talking about the runes, why do you get 16ap@18 for your seals while you say you don't need AP from them ? I think you could get some more usefull runes like :
- 6.85% evade
- 48.15 health (or 9.72 per lvl => 174.96@18)
- 3.87 hp regen per 5 sec
- 0.90 mana regen per 5sec (16.20@18)
- 3.69 mana regen
- 62.01 mana

Mana regen should be good early game (before you get the archangel). As Ryze's skills are not really manavore, the single regen coming from runes should allow you to do barely what you want even realy game.

Concerning masteries, why do you get armor and MR when you could get 5% more xp ? I would also remove meditation an get some regen from runes (0.90 per lvl seems good, same regen than meditation at lvl 1, more after), so i could take the 2% CDR from intelligence and 15% summomner spell CDR (or the last 3% MS with last Quickness point).

Items are good IMO. If i had to take a last one, i'd go Void staff, Will of the ancients, or Banshee, depending on opponents MR and nukes/CCs.