Twice. Its storytime.
I registered by first ID (10541) to the forums on June 15, 2012. I figured I'd just look around for updates and to pick up things from the addons not released on RTB. Well, I found an unruly bunch of awkward teens acting like goofballs and I wanted to get in on it. I found that they ignored the no-avatar noob. What now? I stirred up a giant storm making stupid threads and unintentionally trolling down the boards (notably clan discussion and drama). Once I realized everyone was against me, I defended myself in stupid ways and on top of that created a wall of spam. By June 18, I was permanently banned.
Didn't come back until October 2013 on this account. Thankfully, nobody remembered me (or at least didn't bring it up) so I established a foothold and stayed there. During the whole Okiver incident in November, I got ticked with the way Ephialtes was handling things and blaming the wrong people and put him on the spot. He got mad, so he went searching for a way to get back in some manner. In one of my recent posts, I announced i was bumping a thread that was seven hours old, and he banned me for "Bumping topics" for a week. When i complained, he found a post where I wrote "User was banned for this post" (note it is not bolded, and wasn't for a reason) and laid down another week ban for a grand total of two weeks. Then I went to Badspot who didn't give a crap.