Spinning off of the 8th Doctor main range story, Sword of Orion, Cyberman shows us a glimpse of the Orion War between the humans and the androids, as well as a mysterious man named Paul Hunt, and a secret project called Scorpius.
Cyberman is pretty good! It's definitely not an amazing Big Finish release but it's decent and has some great characters and moments, it's also all free on Spotify! Series 1 was ok and carried by the performances, but series 2 was great all around (with much improved sound design too).
1.1: Scorpius - 7/10
1.2: Fear - 7/10
1.3: Conversion - 6/10
1.4: Telos - 7/10
2.1: Outsiders - 7/10
2.2: Terror - 7/10
2.3: Machines - 8/10
2.4: Extinction - 8/10
Machines is the best one and really the climax of the whole thing, with Extinction closing up some loose ends. Sarah Mowat's Karen Brett is excellent in the first series as she struggles with the war and trusting Hunt and Mark McDonnell and Hannah Smith are fantastic as Liam and Sam, respectively, with their relationship at the core of this series.
A solid early Big Finish release that I would recommend if you're looking for some good 70s/80s-esque Cybermen content that you can easily obtain.