0. clear some camps to get to 15% and spawn the bosses
1. get to kharanos and kill the doomguard boss
2. infernal boss
3. pit lord boss
4. dread lord boss
5. doom lord boss
usually the group splits into two parts, one clearing 1. and 2. while the other clears 3. and then they meet at 4. so everyone losses one or two bosses for no reason. please follow the path and enjoy amazing exp.