NM's HP and Strength is based on the number of ppl on the instance OR number of players participating on the Fate. My party was the last 8 players on the instance farming lvl 37 dragons (with me as a lvl 35 trying to farm lights, the rest lvl 32-33). Eventually Hadhayosh pops, and the group wanted to try him out. The RDM said she/he was willing to use return and raise us if we wiped. So I switched to tank and tanked him while the rest dpsed and saved the LB for the last 8%.

He was much easier and we were able to kill him easily with just us. I was on attack element the whole time and barely took any damage.

A few days before when in a full instance, a different group popped Hadhayosh, a lvl 35 warrior was tanking him and he caused a alliance wipe, dots eventually killed him but we didn't get exp since he deaggroed for a second before dying to dots lol. xD.