Complex sentence: As the game progresses, the player finds out that Tess has used a number of people to gain what she desires, but at a price--something went horribly wrong, transforming everyone on the entire isle into either restless ghosts, demons or the undead.
Split into simpler sentences: As the game progresses, the player finds out that Tess has used a number of people to gain what she desires, but at a price. Something went horribly wrong, transforming everyone on the entire isle into either restless ghosts, demons or the undead.