I saw that there was a distinct lack of descriptive strategies for the undergames that don't require watching a video, and also a distinct annoyance towards the undergames for being so difficult to beat on Master difficulty. Well I wrote this guide on how I beat it, and I'm not a super fast or obsessive player, so if it works for me it should work for most people.

https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=3533064268

Hopefully this helps more people 100 their achievements.