shellshock.io with friends at school!
PigeonProxy lets you play Shell Shockers under any filtering service that uses the PAN-DB filtering and categorisation IP/URL database from Palo Alto Networks (which means, at school!)
Blue Wizard Digital releases alternate URLs for Shell Shockers, and while most of them are blocked, some of them do work!! Unfortunately, there is one problematic issue - it doesn't show you the join link while playing in private lobbies... and that's where PigeonProxy comes in - it'll create a game for you to play with you and your friends!
If you're interested in more information about PigeonProxy, visit the official project Google Doc here.
For an end user instruction manual on how to use PigeonProxy, you'll find the official instruction manual here.