If after I get a personal domain for my forum, someone clicks for instance darksummoner.forumotion.com (my forum), would they be redirected to the new domain?

Yes they would. However, if your domain runs out because you didn't pay your yearly fee the domain address won't direct to darksummoner.forumotion.com until you pay up. Thats why I don't use domain names or link to them.

Alright great, because mine has 2k registers and the old link is literally EVERYWHERE ingame. Im actually getting it free because of activity and will be worth paying for after a year is up.

Ok great. So if this is solved go ahead and edit your first post and mark it solved by ticking the solved icon and send you post. thanks