So many attempts have been made to recreate the effects of morale in
battle for Age of Kings, so hopefully this should be in with the best of them.
This version allows you to upgrade or downgrade 2 players HP and attack (or whatever other effect you want to use) at increments (that can easily be set) by comparing players to see who has the most kills.
It also has a limiter to stop the HP and attack getting out of hand. This limiter (which again is easily set) stops units being upgraded more than ten times, unless they are downgraded.