Cyberpunk 2077's 2.0 update adds an arcade shooter that's basically Doom

gamesradar.com:

Cyberpunk 2077 has an in-game arcade machine that basically plays a version of Doom.

As spotted on the Cyberpunk 2077 subreddit, update 2.0 appears to have introduced one great easter egg. 'Arasaka Tower' is a brand new arcade game that V can pick up and try their hand at, and it effectively puts a Doom-like spin on the events prior to the main game.

You play as Johnny Silverhand, storming the titular Arasaka Tower a few decades before Cyberpunk 2077 takes place. You can see gameplay just below, in which Silverhand stalks the corridors of Arasaka's headquarters, gunning down corporate troopers and katana-wielding warriors, of all things.

What CD Projekt Red has done here is pretty genius. They've taken a legendary event in Cyberpunk 2077's world - the day Johnny Silverhand and company assaulted Arasaka Tower with a nuclear weapon - and turned it into an actual in-game arcade title recapturing the prolific events.

Let's just hope there's no one playing this who lost a relative or friend in the bombing of Arasaka Tower. The game ends with Silverhand setting off the nuclear weapon and fleeing in a chopper, which didn't actually happen in Cyberpunk 2077 - the rockstar was gunned down by Adam Smasher instead.

This is all apparently related to a mystery in Cyberpunk 2077 dubbed "FF:06:B5." This Reddit thread is dedicated to solving the "mysteries of the Cyberpunk 2077 world," which apparently include this mysterious line of code that points to wider secrets of Night City. 

How the Arasaka Tower game factors into this is simple: the first screenshot in the Reddit post embedded above is a statue that can be found in the arcade game. This is actually a representation of a statue in Cyberpunk 2077 itself, which has FF:06:B5