Unlike Taylor, the fun protagonist you talk to and advise in Lifeline, Silent Night, and Halfway to Infinity, Wynn in Flatline is an annoying and whiny nuisance. Complaining, ignoring your choices, and, taking minutes to perform the simplest of actions (opening a door?). The story does expand the Lifeline universe in an interesting way, answers some lingering questions from Taylor's games, and the heart-rate monitor is a neat new mechanic, but it's still a bit of slog to get through.
One part of the game requires you to access an external website to get some codes: that website is now shut down. You can now get the codes from https://pearsoncorp.green/ or https://twitter.com/Lifeline_Server/status/1076294978190622721