RecyclingAlthough the developers claimed to have created "all new aliens and guards" for Planet Strike, if you really look closely you can see that the "new" guards are really just the original three guards, recolored a bit to look more alien-like. Similarly, a lot of the "new enemy sounds" in Planet Strike are the same sounds that existed in Blake Stone: Aliens of Gold, just played backwards.
Source CodeOn July 9, 2013, Apogee released the source code for Blake Stone: Planet Strike!; almost 19 years after the original release. The source code was long believed to be lost. It can be downloaded from http://www.apogeesoftware.com
Information also contributed by Frenkel