multiuseのコメント

If your health does not fill up automatic: Reach a city/castle - reload game/page - full health

My STRATEGY to prevail in HARDER mode: Try to expand the first five days as fast as possible, leaving no defense behind. Afterwards, try to scout at least 2 squars each days and look out for a school. I put all my manpower to become soldiers. Having 19 soldiers turned the game around, and I was able to conquer the the evil graveyard. Although I wanted to win it by closing the gate I immediatly stoped, as it would have left my defensless. Eventually I won the game via research while my soldiers fend of the zombie hords. Beware, as you getting your research to an end, the hords will attack more often with higher strength.

Same problem as everybody else: No medium badge even after wining the game several times.