score:5
As a tourist you cannot obtain an ARC, because it is for residents, not tourists. Since you don't reside in Korea, you can't go to the Immigration office in Mok-dong and ask for a resident card. You'd need to enrol in a language course, for instance, or find a job.
Note that if for instance you enrolled in a language class, say a 6-month course while in Korea, you'd have to take a few points in consideration: