Your actions affect the larger story, is a really good selling point to other similar style campaigns.

Aside from the clock/tick system (already mentioned) the biggest thing that stands out to me is the spell system.

1.) You know spells X, Y, and Z. There's no "you can only cast so many spells per day, and only if you memorized them when you woke up" crap. You can cast as often as you like, but frequent casting causes damage.

2.) You don't need to memorize 6 spells that are only slight variations of each other. Acranis uses adaptations for spells you already have to make them hit more things, go farther, last longer, etc...