Kai_Mao on 10 August 2016
Probably would've been best to utilize different assets (or completely different characters, environments, and enemies) from stuff from Zero Mission. Granted I haven't played the original in a long time nor have played the remake to see if they used Zero Mission assets or something similar.
All of these things about copyright/trademark are becoming less black and white than I realized. Especially, since we're dealing with an international IP.
