Shadowrift also features monsters that don't merely sit waiting to be slain; if you leave them alone, they will rip Haven Town asunder. They'll kill people, break walls, and kick your heroes in the face. Combat with them is intuitive (though frequently painful). For defeating a monster, heroes gain Heroism, a simple, consistent boost to their power that makes them better at anything they undertake. Since the monsters won't stop coming until the last Shadowrift is sealed or the town has been built into a mighty fortress, you'll need every boost you can take.
The second edition of Shadowrift features many improved mechanisms, including a revised system for how monsters choose who to attack (based on types of villagers, instead of specific people) and a new system for monster powers (making them much more dangerous). It also has a revised card layout and a great deal of new and improved artwork.