Been checking up on this guy, seeing he should be around level 40, I gave it a go as a BLU/RDM level 55. Ouch, he did hundred fists several times, paused for a breath, and started pounding again; also did a few Shoulder Tackles especially towards the end, lol (seemed to have those ready very fast). I was never really worried but had my Tactics Pearl ready and poped my healer NPC halfway since I was in a hurry. A lot of HP so I used my spells mostly for skillchains, debuffs and a few head butts to stop him up a bit.
And the pumps I will use for some jobs 35 to 37 one day and maybe levelcap-things, but for now my mithra mannequin will have them on (hope they match her santa suit).