I am not sure if this is confirmed or not, or have been talked about, But after spending a hour or more in one zone, Or not sure if it's even time based or amount of kills that make it occour. The thing is. IT suddenly spawn's elites, yellow's in crazy nummbers contantly respawning for a short period of time, and as solo, it's impossible, even if you kill 30 with an rpg very fast, it wouldn't keep up with the spawns beings made. If anyone else have experienced this, Please do share. P.S: My english sucks : P