This is my standard Ryze Build, I tend to be aggressive early game and really punish the champions ryze counters.

I feel like 1/3/26 is the best mastery allocation for ryze, some guides will say 9/0/21 for the 4% cd and magic pen% but you miss out on the 6 MR and i feel like 0/9/21 for extra hp isn't necessary. with 26 points in utility as opposed to 21 you gain alot, you can get the full movespeed, mana+manaregen, spellvamp, 6% cdr and very importantly Strength of Spirit for 1% mana to hp/5. roughly 6-50hp/5 while ryze levels up.

For runes i have chosen Flat 10 Magic pen to reach 30 with sorc boots and 3% movespeed for Q harras and landing snares. I have taken Flat Mana and Flat Manaregen for the low level boost in Q damage and to help ryze with his early game mana issues, you can really harras alot more with this, which helps for mid champs with good sustain.

Item build is pretty standard, I hardly ever wait for tear+boots, I prefer to go back earlier and get tear with 1-3 pots to keep up early game pressure. Sorc boots over Merc treads nearly every time, you will need the damage boost by this level. I really hate guides which recommend getting sapphire crystals to boost damage, this will just leave you being squishy. I prefer health crystal if i am doing well or Negatron if i am having trouble with the mid, Chain vest for an earlier glacial shroud is also a good option. after BV+FH Will of the Ancients is the strongest item choice, you can complete AA staff before or after WoTA. Abyssal Scepter can be substituted for void staff
I would not recommend RoA or Rylais.

Late game you should be farmed up, at least 10 kills above everyone else and you will get a penta-kill soon, never forget that you are playing a GodMode Champion and you can probably 1v5 their team while tanking turret fire.