Combat music is from Remnants of Skystone I think, spoils screen music is unsure, and music of world map is definitely from somewhere else... I couldn't recall...
One small tip: While you can't initiate rainbow laser in air, you can start charging on the ground, then jump and release it the air. This allows you to clear enemies before jumping onto platforms.
You need a very high level assassin for the last four challenges, since it is the only class which can deal really HUGE damage and possibly scoring a kill every shot.
The range boost is somehow bugged: If you have enough range bonus from chargers, different guns will have different caps, for example the light bringer caps at about +20 range. If you upgrade +1 range bonus it gets to +21, but if you do it again it falls back to +20. It makes sense if it has a cap, but falling back?
It is really difficult to tell which of my ~50 units are getting low on health in the heat of a battle. I lost several rank VII guns because of not noticing they are getting hit often.
The hard badge requires more patience than anything: If you wind up your snake slowly it is pretty easy to get 42 pts, just that it could take a very long time.
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 "Enigmata: Stellar War"){kind=icon}
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 "i saw her standing there"){kind=icon}