[atanasb]

I was wondering the exact same thing.

EDIT: Here's what they are saying about Unity:

"We never had a Unity port for Frontiers. Origins is coded in cocos2d, like all the other KR games. By the time Unity became known to us, we gave it a try with the Steam version of Kingdom Rush. This was mid 2013... Frontiers was almost ready by then. Early 2014 we started working on Origins and we used the old engine out, sine the effort of adapting the old games to new platforms wasn't exactly good to us. Origins is the last game that will use our old and loyal cocos2d engine. As we define what our next game will be, we are very much aware that it must be multi-platform."