Mercurius, I don't mean to belittle you but I have never seen you in any game and thus I can assume that you are not in high ELO play (when you start seeing names like Dan Dinh, Dyrus/I Play Jax, Classick, TreeEskimo, etc. in your games then you can safely assume you're somewhere near the top).
As far as KingofTown's creep observation goes, if you throw Ryze's ult at a hero within a bunch of creeps you'd be lucky to get more than 2 bounces to hit on your intended target (if you happen to get a kill you have to blame that on pure luck and you might as well go buy a lottery ticket then).
If you had 240 MR and somehow a Ryze solo'd you with his ult then he must have had a ridiculous amount of AP that I'm not even sure is possible in this game (maybe you just had 240 MR but no HP to back it up though I find that really unlikely). It is your fault for letting him get that farmed when he is so easily ganked. He's one damn squishy champion and if your team is not smart enough to focus him down early then that is a simple mistake that your team made. As with any other glass cannon type champion, Ryze cannot simultaneously do ridiculous damage while also not dying in less than 2 seconds of focus fire. The best any Ryze in a high-level game could ever hope is to make the fight a 4v4 not a 5v4 (in other words getting a kill usually means getting killed for Ryze). Ryze is overly cooldown dependent and he often times cannot even live to cast a second Rune Prison or Overload. Also Rune Prison does not stop spell-casting which is a big downfall.
Trust me, Ryze was my main when I first started playing this game and I found out the hard way how poorly his ability set scales into the higher tiers of play. I can still sometimes run off games where I get a ridiculous amount of kills with Ryze because he is one of those heroes who feeds off a good early start. Just ask Shirokuma as I went 33/7/10 a few days ago with Ryze, but I was only able to because the other team allowed me to feed off them early and they failed to focus me in team fights.
If you feel like playing a game, add me on friends I play on my account statikk typically.