The Stanley Parable: Ultra Deluxe is a sequel of sorts to the original Stanley Parable game, with the new release came some familiar achievements, including the ambiguous '8888888888888888' achievement. The description of this achievement doesn't help players solve it at all as it's just a larger set of repeating 8's, but this confusing puzzle is actually quite simple to solve.
During the course of The Stanley Parable: Ultra Deluxe players will be weaving in and out of office areas while listening to The Narrator, who is guiding their way. There are many different paths that a player can pursue throughout the game, and even more have been added with the new Ultra Deluxe edition. For this particular achievement, players are going to want to follow The Narrator's instructions up to a point.
Starting off in Stanley's office, the player will want to follow the set path through the cubicles. Once the player comes to the two doors, The Narrator will instruct them to enter the door on the left. Follow that instruction and head towards the Meeting Room. Once there head to the back-right corner, this will lead the player through another set of hallways. Ignoring the Broom Closet follow the hall until reaching the stairs. The Narrator will then instruct the player to head up the stairs to the Boss's Office. Follow instructions and head up to the Office Lobby. Ignoring the Executive Washroom on the left, turn right and then head to the left door and enter The Boss's Office.
Where to Complete The 8888888888888888 Achievement in The Stanley Parable
Inside the Boss's Office in The Stanley Parable: Ultra Deluxe is a keypad along the back wall, The Narrator will eventually instruct Stanley about the correct code to input into the keypad. Ignore him and instead only punch in the numbers '8888' into the keypad. After the first attempt, it will flash red, showing that the code is incorrect. Continue to put in the code '8888' a total of four times and the achievement will unlock.
Despite the confusing name, the '8888888888888888' achievement actually does tell you exactly how it should be done. Entering '8888' into the keypad 4 times equals sixteen '8's. This is just another example of how silly The Stanley Parable: Ultra Deluxe can be, there are constant inside jokes and meta humor throughout the entire game. After the achievement is completed the player can continue on with the game in an attempt to find another new, and oftentimes weird, ending.
The Stanley Parable: Ultra Deluxe is available on PC via Steam, Xbox Series X|S, Xbox One, PlayStation 4, PlayStation 5, & Nintendo Switch.