Amanda in the Reverse Bear Trap, struggling to get free. It added tension to the close-to-death experience and started what the franchise became so iconic for. The scene was adapted from the original short film that preceded the movie, and wound up featured on one of the promotional posters, making it an example before the film even came out.
John Kramer, the real Jigsaw, rising from the pool of blood after Playing Possum in the Bathroom the whole movie. To this day, it's hailed as one of the most unique and memorable twists in not only the franchise, but the history of film in general.
The shot of Adam and Lawrence on their bellies, the former sobbing and the latter trying to comfort him by pressing their foreheads together and talking to him. It's frequently homaged and used to represent the film as a whole, not least of all for the inherent Homoerotic Subtext.
The Needle Pit serves as one of the most iconic traps in the series, helped by it being one of the hardest traps to watch, even with it being nonlethal.
The Angel Trap, the Freezing Room and the Rack have become some of the most memorable traps in the series, on account of them being arguably the worst to die by.
The Shotgun Carousel. Creative, tension-filled, gory, and over-the-top in a way that worked, it's a memorable scene that combined a lot of elements from previous films and spun them in a way that felt original.
