It`s as SirWhiskers said. When you get to Elinia check first location you visit , there is druid shop who will give you quest to feed his pet egnum and in you`re inventory will be little creature egnum from then on. Go to valley of 1000 rivers and pass over all little black clouds you can find, egnum will eat them and when you right click on him in hero screen sohul tell you how full is he. Best to wait untill he gets `piged out`
, and then return him to druid shop where you found him. You should get 8 runes for this (8might for warrior, 8mind paladin class and 8magic runes for mage hero). Have fun
EDIT : And why didnt you take other 2 rage spirits ??? In hero screen you posted on start of tread click on pictures of rage spirits and they will tell you what to do for their service. Talk with them and get their allegiance for Zerock you need to fight 1 fairly easy battle, and for Sleem you need to have around 20 royal snakes (or some other poisonous unit snakes, poison spider) to give to him to eat, after doing those you`ll get 2 more rage spirits both with great skills, that you lvlup by using them in battle.