The game was great fun. Even though I didn't got through all levels. Sometimes it felt a bit punishing (Having your shadow past darting next to you could be a nice way to see how you actually progressed would be fun). Adding more features like upgrades or even downgrades for more point could be an option, too. Maybe controlling more than one could also be interesting. For example as an easy mode, where all or a just one previous runs walks with you and you can see whether the you and your past together could be enough to overrun the defenses.