Finally, there is a hidden end to Cyberpunk. It serves as the ultimate challenge in terms of difficulty. To unlock it, you need Johnny to like you, which isn't an easy compromise to find. You have to be nice to him during the various in-game events, for example while smoking, but without playing the fanboy either. You also have to be honest during the series of missions that concern him. When going to his grave, he should not be called a legend, nor be cruel.
Then, after the point of no return, go to the roof with Mysti as always, but when she's left you to think about your options, don't choose any response when talking to Johnny. Wait a few minutes and he will offer you a suicide mission: attack Arasaka Tower solo to reach Mikoshi. The thing is obviously very difficult, especially as both automatic and manual backups are disabled on this section. In case of death, you will go directly to the end credits and then to the point of no return.
It's therefore better to have familiarized yourself before with the end-game fights and in particular against Adam Smasher, have an effective strategy against him.
Original content by Robin "Raiden" Bouquet.