This is my first time browsing the forums to any real capacity, however, I was told going here would be the best way of trying to resolve my problem.
A few days ago, I installed the most recent patch to SK for Steam, and the patch went along fine, as it usually does. The key thing here is? The game refuses to boot at all, due to it not being able to under the Java virtual machine. I uninstalled Java, reinstalled it, made sure it was the most recent release as well. Still can't get any farther besides it not being able to boot the Java virtual machine.
Is this a common issue for anyone? I disable the Steam overlay since that often crashes the game for me, but this is the first time I've ever seen Spiral Knights absolutely refuse to run in the first place. I'm not angry by any means of the word, just worried and puzzled about this, since I do not know what caused the game to refuse being launched.
Steam SK use its own java, you can find it in sk app folder named "java_vm"
So it doesn't care about your manipulation with Java you download by yourself.
Well you can manually replace java in SK folder with downloaded one. I'll just copypaste here solution, posted over9000 times on this forum.
steam pc:
You can also try the same with other versions of jre if current not working properly.
Special thanks to Thrillhaus.