Fire Phase

[Silverkiss]

No...
No one needs to build a huge amount of units, if you do that you will win anyway. The matter here is that the power of all the civ´s "heroes" (units with high exp) will be together in one unit, making victory easier (unless other civs had many "heroes" too, because if they had, their avatar will be powerfull too)

 

[MrManNo1]

An easy way to do it would be to keep a tally of all the exp that all of your dead units had. That way, you only need to store a number, instead of each individual unit. Then, you can give the avatar 25%, or 50% of that experience. Plus, you can allow avatars to access special bonus promotions, like Heroic Strength 3+, or the promotion in Warlords that increases experience gain.

You could also allow the avatar to gain 1 extra experience for each "heathen" (units from another religion) he kills.