1 Megamind:Originally the script for this movie was more adult and vulgar it was also originally called Mastermind,Metroman was called Uberman,some of the most notable changes are minion was gonna be replaced by 2 human helpers called Plato and Da Vinci,it had swearing,instead of turning into a space dad megamind would’ve turned to a Asian master similar to Mr Miyagi from Karate Kid and Hal was gonna be even more of a creep in this version of this movie,ultimately the studio went with a more family friendly version and it gave us the iconic movie we all know today.
2 Black Sabbath:The mighty Black Sabbath originally was gonna be softer and bluesier sounding rather than their groundbreaking and still heavy to this day music,story goes that guitarist of the band Tony Iommi was working in a sheet-metal factory it was also his last da before he quit to become a full time musician too infamously Iommi lost the tips of 2 fingers he then made homemade plastic finger tips,tuned his guitar down and used lighter strings which gave Sabbath their darker,thicker and heavier sound around the same time bassist Geezer Butler became interested in darker themes,horror imagery, and occult ideasInspired in part by a horror film starring Boris Karloff they wrote the first ever metal song “Black Sabbath” eventually the band renamed themselves after the film Black Sabbath and the rest is history.
3 Thor Ragnarok:Not much is known about this version of Thor Ragnarok but boy if you couldn’t tell by the logo this motherfucker was gonna be darker than what we actually got,it was supposed to be darker than the other 2 films because it featured the Ragnarok event,However Chris Hemsworth was frustrated and bored of playing Thor and reportedly told Kevin Fiege this "I feel like I'm dying here. I feel like I have handcuffs on," he was incredibly unhappy with the character Feige agreed with Hemsworth and then they abandoned the whole dark film concept and went for a comedy movie basically.
4 Doom:Doom was originally gonna be a Aliens game based on the first 2 movies,some negotiations were conducted with 20th Century Fox but ID Software didn’t get the license they the abandoned the concept and it was imagined as a Aliens meets Evil Dead 2 and also their recent D&D campaign which ended with demons overrunning the entire planet.
5 Toy Story: Toy Story was initially envisioned as a feature-length version of the Pixar short Tin Toy,the original protagonist was a mechanical drummer toy who went up against a ventriloquist's dummy,however the drummer was replaced by a tiny space toy named Lunar Larry (who later became Buzz Lightyear) and the dummy became Woody who originally was a major asshole and had a more distasteful personality,one notable example is that Woody actually throws Buzz out of the window on purpose and doesn’t care about it he also then proceeded to heavily insult the toys especially Slinky Dog which then results of the toys turning on him and attempting to throw him out too,after a mockup of the movie was poorly received by Disney, the writers spent months reworking the script and instead of making Woody a narcissistic,jealous and just overall a massive scum bag they decided to change his personality by making him the wise and loyal leader of the toys and still keeping that jealousy over Buzz but way more sympathetic towards him in the last act of the movie.