Recently me and my buddy encountered a glitch in MoO2.
We played a multiplayer game, where we both arrived at a starsystem protected with a dragon at the same time.
He was the 1st player, i was the 2nd. Not sure, if it counts tho'.
So the dragon attacked me, and left my buddy's scout alone for the turn. He stayed there for the next turn, had the option for "engage enemy forces" against the dragon :D But he remained idle. Next turn however the beast attacked him too.
I was wondering, if he wouldve sent a colonyship too, wouldve been he able to colonize in that turn, or not ^^

Attached the picture with him orbiting with the Dragon :D

Monsters (aswell as other fleets) attack only once per turn, so if more than one player arrive to a monster system - only one would be attacked. Despite it no colonizing activity is possible, as monsters in a state of war with you (effectively, they blockade planets, and prevent colonizing in theyr presence). Mere fact of orbiting with dragon is similar with orbiting with eel, the real curious fact is what you can steal a system specials from a monsters without actually destroying them...

Ahh , now that you wrote it, its actually quite obvious :D

Also what do you mean by stealing? Like space debris, and such?

Yes, any one-shot system special (all exept natives or deposites, which require a colony to be built to be used).