I think by now, all of the admins on here automatically ban for six months, sometimes shorter for some cases, other times it is for longer. Here are two cases where I will make it longer.
Today, I encountered the first case of someone griefing another user's user page. If you grief someone's user page, you will be banned for a year. No exclusions and no getting out of it, unless if another admin decides to do unban you.
I also found a case where the same person repeatedly griefed the same page during the same day, after each time someone fixed it. You will be banned for a year. If all you want to do involving this site is to damage the information in it, you don't deserve to be here.
Finally, a case where I will ban someone for a shorter time, is if I'm not sure they meant to damage the page. If you look at the edit history to Mo' Creatures, you'll see that in one edit, someone added almost 3000 characters. When I took a look at it, it seemed like they tried to add some formatting to the tables, but failed miserably. If it was an accident, and you read this, you can get back on in three days and let me know, and if that is the case, I'm sorry.