As it's at work I suggest not trying to bypass it. If work don't want you to be on a game or a certain website it's best to follow that.
Your IT department keep logs of every website you visit, and programmes you open/download. If you visit a website you shouldn't or run a programme you shouldn't it will flag in their system and you will get found.
Luckily for me we're allowed to play games during our break. And as I work in an IT related job pretty much everyone plays a game
(good'ol IT stereotype)