Summary: You've seen the universe where Bruce died in Crime Alley instead of his parents, Thomas became a version of Batman that kills and uses guns, and Martha was Joker? What would happen if Martha was the only one that died that night?
diffrences
Bruce became Batman in high school.
Thomas tries to drown his sorrow by alcohol and women.
Thomas is violent towards Bruce while under the influence of alcohol.
Somebody other than Jack Napier or Martha Wayne will be Joker. (You'll find out who eventually)
Bruce meets Selena Kyle in high school.
Richard Grayson's the younger half brother of Bruce Wayne.
Bruce went by another 'hero' name before becoming Batman. (Might remove this one when I actually write the chapters)
Simularities
Harleen Quinzell still becomes Harley Quinn
Selena still becomes Catwoman
Dick still becomes the first Robin
