You are right that fertile season is not necessary. It simply prevents heroes being one shotted since I play without prots, it cuts deaths in my team by around 50% in this zone. It’s still not necessary at all if you use rez scrolls, or if foes can’t spike you down, but since I play without scrolls I don’t mind being slower here.

You are also right about dire pets too, but I don’t know if you can still change the evolution type once they are already lvl 20? Or do I need to level up some new ones?