this happened to me too lol. totally wiped out my whole colony, insanely strong. i just disable this event from happening in the mod options.

I go straight to dev mode and destroy it. I'm not sure if there is any viable tactic to take them out the natural way (maybe) unless you build your colony with that in mind exclusively.

How are elementals strong in any way? Their armor is paper thin and they go down almost instantly. Granted, I do use CE.

you use CE

There's a wide variety of opinions. Generally when half of the feedback says the event is too easy and the other says it's too hard, then I evaluate it to be just about right. However, in the next update I will decrease the difficulty for the easy setting, the moderate setting will remain roughly the same, and the hard setting will become more difficult. Hopefully this will satisfy both sides.