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Dr. Loomis' Badass Decay is the result of the ending Halloween 5: The Revenge of Michael Myers
In Halloween 5, Loomis is still hardy enough to survive being thrown through banisters, down stairs, impalement and stabbing from Michael. Meanwhile, in this film, all it takes are small blows and he's down for the count. This is presumably the result of his stroke in the end of 5. Dr. Loomis' limp was also affected
There's gotta be a reason it switched legs. Halloween 7 would’ve been about Dr. Loomis and his journey to stop Michael and to free himself from the Cult of Thorn
If not for Donald Pleasence passing away in 1995, the massive reshoots that changed the ending after his passing, the mediocre performance at the box office,and Jamie Lee Curtis returning as Laurie Strode for H20 as a Continuity Reboot to the series, then the 7th film would’ve served as a proper conclusion to the Cult of Thorn timeline where Dr. Loomis finally finishes off Michael Myers and freeing himself from the Cult in the process. Jamie’s adoptive parents were the ones that got Halloween banned in Haddonfield
After the death of their daughter Rachel, combined with the sudden disappearance of the adoptive daughter Jamie and the two years that Michael Myers spent massacring the small town, they petitioned for the banning of the holiday and successfully got it banned for six years. Cochrane from Halloween 3; Season of the Witch is another member of the Cult of Thorn
With him having died in the events of that movie Wynn abandons the quest to return Halloween to its' pagan origins and seeks to exploit the supernatural power for his own ends.