Besides being a tower defense game its nothing like Aigis.

The op mentioned it being inspired by Kingdom Rush: Origins and that is true. They literally copied that game (all the numbers and upgrades from the towers are the same) and added some small stuff to it.

Basically you have 4 tower types that can be upgraded (into 2 variants each eventually) compared to Aigis where every single girl you got was a tower you could place on the map.

Oh well, its not a bad game. They game they copied is fun after all. Aigis was so much better though... (still bitter about its closure).

The current version is pretty fair. You can farm the current roster of heroes through missions (very slowly) and there isn't anything too much pay to win. You can get everything so far just through grinding.

How they'll do events is the question. Games on Nutaku have a habit of ruining the games through stupid event designs so I'm a bit pessimistic.