Indie game storeFree gamesFun gamesHorror games
Game developmentAssetsComics
SalesBundles
Jobs
Tags

Could you clarify how a morale roll is determined when an enemy reaches half their HP? 

Using whatever morale system you prefer. The easiest is a 1d6 roll where 1-3 is fleeing and 4-6 is stay and fight. If you use monsters from other games as recommended you should use the morale rules from those games.