The end. First, after his first escape from the lab and his rescue from the Clowns by Kaneda and crew, he gets assaulted by horrific flashes of the future, including a nightmarish hallucination where he falls and hits the ground and spills his guts onto the ground and tries to scoop them back up.
There's the nightmare scene. After undergoing the experiment, Tetsuo is left to recuperate in what looks like a child's bedroom. He wakes up to see all the toys come together and form some kind of gigantic teddy bear with a monster-like right hand and a milk-spewing toy car that proceed to try to kill him.
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Awesome) • 
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