We just had this on Bahamut. All I have to say is wow.
There were 6-7 "waves" of monsters. Unlike lvl1, they had 4 mobs each.
Mobs had alot more magic defense/hp. They were alot tougher to kill and hurt.
Lasted a ton longer.
Some other stuff im sure other will fill in. There were around 180 people on Bahamut and it was a ton of fun. Everyone was really happy about it and managed to get stuff done besides the usual "omg they died so fast". At the higher levels I can imagine this being alot harder.
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