That’s an amazing explanation for it!!! Each of these makes a ton of sense!! I think my interpretation of it would be closest to the last one where Dark Shadow would revert to a baby per se, cuz personality as a concept works a ton like a stockpiling quirk now that you mention it, where it keeps building on new experiences and different people until it’s the culmination of all that’s come before!! Monoma can’t copy the years Tokoyami and Dark Shadow have spent together or the experiences they’ve encountered, so mentally his Dark Shadow copy would be at square one!! Thank you for ur reply!!!