Hotel 626/Asylum 626 (lost series of online browser games; 2008-2011)
Hotel 626 was a browser game released on October 31, 2008 while the sequel, Asylum 626, was released a year later. Both games were made and published by Snack Strong Studios which was a fictional studio that Doritos came up with. They were intended as a Halloween marketing stunt to bring back their "two dead flavors", those flavors were "Black Pepper Jack" and "Jack and Smokin' Cheddar BBQ". As a result of this stunt, both games became well-received at the time because of its unique premise and its nature.
In order to play either games, they have to be played specifically around 6PM-6AM (though its possible to play it anytime by simply changing the internal clock of your computer). The first game has you running around the haunted hotel to escape the place while you encounter and deal with hostile entities along the way. These range from spooking a possessed maid by using the camera's flash on her, lulling a demon baby to sleep by spinning the music box correctly and then carefully balancing yourself against the floorboards so the baby won't wake up and kill you, solving a cryptic coded puzzle to escape a room with an unknown individual beside you strapped up with a straight jacket, browsing through the photos of people and clicking the right picture which leads you to the next room, and running through the hallways while a voice guides you to the exit. Entering your phone number in-game would get you an actual phone call that does the same thing. Once you do that, you'll get an actual phone call at the middle of the night that tells you that you haven't really escaped the hotel.
The second game however, is very different from the first game in that rather than escaping the hotel, you are in an asylum being operated by doctors while bizarre footages play. One of the interactive aspects of the game involves you dodging the chainsaw of some unknown murderer while hiding in the closet after they killed your parents, looking at the dark waters of the sink, keeping off entities by using your flashlight, and choosing who to sacrifice.
Because both games were essentially just advertisements, they were only meant to last for a limited time before they were inevitably got taken down by the creators somewhere around December of 2011 as evident by the Wayback Machine archives of the website. As a result, the game is unplayable and can only be experienced through gameplay videos uploaded to YouTube.