I'll either start trolling until the account gets blocked or deleted or I'll sabotage it as suggested above but one way or the other it'll be finished.
What is that going to benefit you, even if you plagiarize and get banned, it does not mean your account has been deleted. If i were you, i'd set a random strong password and i would not back it up, then forget about the account for good, it is much better than wasting your time trolling here. You can also announce your exit from the forum, and tell users to leave a neutral feedback that if the account ever becomes active again, then it has been compromised.