How do different repacks function?

[swedishchefborkbork]

Hello,

For example, are any MoP repacks more stable with Cata content? If so, how can they be more stable compared to Cata repacks? Or WotLK content in a Cata repack? I have not DL'd one yet, but I wanted to understand how different versions can work together.

Thank you!

 

[Blackvision]

Not sure if expansions can be merged.
But the wotlk core has been worked on for Manu many years.

I don't think that there're any playable MoP repacks out there.
But to add something to your thread, i too would like to know if the different cores are merged together to get previous content to Work.

 

[roja7011]

Although many would suggest that their release is unique, most seem to have taken work from previous databases