I wasn't certain if the "ring events" were a requirement to advance or not but after killing one ring event for about 45 mintues I'm convinced they are optional.
The first ring event (Left Path 3) I killed well over 2000 monsters and noticed the ring event start over many times. It was nice for getting candies for the treat trader I suppose but completely unnecessary to kill them.
The second ring event (Right Path 4) I didn't kill at all and the doorway still opened when the left path finished the puzzle. Jado818 (talk) 23:26, October 20, 2013 (UTC)