After this last mob event, I received the message 'Sanctuary of Saerielle: Town Protected' twice, and also received the rewards twice (for a total of six event satchels and six badges). Not sure if anyone else had this issue as well, or if it was something on my end? I haven't accepted the rewards yet. :3

Krin just mentioned this in chat. Essentially it means two people just killed the boss at almost the exact same time. It's not intentional and will be fixed at some point in the future.

What Ash said above, EXCEPT - the issue will probably not be solved at any point soon as it is a very minor issue (not worth the time atm)

So I guess just enjoy the extra satchels for now

I would say your pretty lucky, I'm sure at this point everyone can keep what the earned, but its if its being fixed on, it'll prob never happen again.

I honestly still don't know what will happen to events once the new exploration system is fully released.

We will still have them, I just do not know what form they will be in.

But for this problem, it's because most events parse when the user defeats the boss. So if two users defeat the boss at the same time, both will parse if the 2nd person defeated it before the first person's script finished.

With events like the holiday events, that is actually parsed server-side so it doesn't happen. I've just been lazy to change the old events to this way. :\