rare monster spawn?

[dragonteron]

Yesterday I was playing her secret mission on c rank with a random group. there was a lvl 18 a lvl 24 a lvl 56 and me a lvl 63. when we got to block two i went strait the other three went left then i hear the lv56 starts yelling

WTF this monster is actually doing damage to me it looks like one of those things from moatoob help me its lvl 60 WTF why are you guys just standing there

then he died the mission ended and i dont know what happened. so i was wondering if anybody has encountered anything like this.
I mean i have never seen a lvl56 get taken out that fast by a c rank Komatoze (if i spelled that right)

[Kaydin]

There's a few of them in that room, at the same time. He probably got ganged up on, frozen, and beaten to death. :/

[beatrixkiddo]

In block two going left at the very beginning of the block, there are four Gohmon, then one Kamatoze. It's not even a buffed one, so I doubt they could have died to it that easily.