I'm fighting these as lv 75 blm with just staff to build tp for spirit taker this SoB is only 34-44 and at 44 thats 31 levels below me, and it manages to drop my hp from 977 to 307.
It crit hit me for 77-82 damage 6 times in a row with out missing, most of the other Young Opo-opo I fought in this area missed most of the time.
Ok, I was lvl 35 rdm/17whm with my NPC companion. I was training in the jungle near the outpost when I saw the dc monkey. I put up a few buffs (not stoneskin, I should've it may have helped) and attacked it. It went ******* on me. I don't need to describe the battle but lemme just say I ran to the outpost and teleported away with 1/2 my hp and <10 mp left. What the? I'd recommend adding a rating to any check status. These guys are tougher than they look.
Killed 5 Young Opo's and got 2 Elshimo Coconuts to drop... Searched this site for Coconut and got nothing. I'll post effects when used after my food effect wears off.
Actually, it is possible to charm them. However, the charm will only last about a second and then you're going to be dead.
I went with lvl 2 BST into Battalia downs to bloodport, so I used Charm on a Sabertooth tiger. To my surprise, it actually charmed it. However, the charm only lasted a second, if that, and it killed me.
You can read on the BST forum or ask a BST, it is possible to charm IT monsters but the charm won't last long at all. You'll be murdered when it wears off.