League-of-legends – I played mid against a Ryze as Kassadin and got destroyed

He is actually very easily countered, as he specializes in countering standard mid mages, you just need to pick less common things to counter him, which does not happen as much in solo queue.

For instance, Fizz, Talon or any AD carry all counter him quite easily and make his laning phase quite miserable.

And if he gets behind, he needs to roam to get kills, and organized teams are a lot better at avoiding random jumps from him, due to warding, enhanced map awareness and better communication.

So essentially, it is too complicated to get ahead with him in a tournament and isn't worth the risk.

I had the same problem as you a while back, you should check this out:

Marks - Red

• S-Rank: ArP, MrP
• A-Rank: AS, CrC, AD, ArP&MrP
• B-Rank: MR, Armor
• C-Rank: AP/lvl, MP5, Mana/lvl, CrD, AD/lvl, AP, HP/lvl
• F-Rank: HP, Mana, CDR, MR/lvl

Seals - Yellow

• S-Rank: Armor
• A-Rank: MP5/lvl, HP/lvl, MP5
• B-Rank: Armor/lvl, HP, AP/lvl
• C-Rank: +%HP, Mana/lvl, HP5/lvl, HP5, MR/lvl, AS, EP5, EP5/lvl, AP, GP10
• F-Rank: CrC, AD, Mana, MR, CDR, AD/lvl, CrD

Glyphs - Blue

• S-Rank: MR, AP/lvl, MR/lvl
• A-Rank: CDR, MP5/lvl, AP
• B-Rank: CDR/lvl, Energy, Mana/lvl, Mana
• C-Rank: Energy/lvl, MP5, AS, HP/lvl, Armor
• F-Rank: MrP, CrC, AD, HP5, HP, AD/lvl, CrD

Quintessences

• S-Rank: AP
• A-Rank: MS, ArP, AD, HP, HP5, Armor, MR, Life Steal
• B-Rank: MrP, Energy, GP10, AS, CrC, CDR, Spell Vamp, ArP&MrP
• C-Rank: AP/lvl, HP/lvl, MP5/lvl, MP5, EP5, Mana, CDR/lvl, +EXP, -Time dead, +%HP
• F-Rank: Mana/lvl, CrD, MR/lvl, AD/lvl, Armor/lvl, HP5/lvl

These are the rune tiers and you should pick runes from the S, A or B rank to get the most out of your runes.

I hope this helped!