Hearts of Iron 4 has some interesting mechanics with the main one being how they handle nuclear bombs in the game. To be honest we all know how bad they are in game and really not worth the investment you put in to get them!

Anyway I have some other videos that are worth a watch:
https://youtu.be/25Nv1_AYrW4
https://youtu.be/ZqU8zLdn3Ko


Other Content Creators made these:
Bo: https://youtu.be/exoPmBsGmaQ
Rimmy has his big stream: https://youtu.be/x8Vv8qAQCS4
ISP: https://youtu.be/H9_mgRtS-io
Feedback: https://youtu.be/bfF5_nxmGbE

My discord for friends: https://discord.gg/u9YEAY