Hi, please see our Collection Rules. It's true sequels only which means thematic collections should not be added. Thanks.

Hey bylineker. I can see your point, however there's this collection https://www.themoviedb.org/collection/140760-final-fantasy-vii-collection?language=en-US where the movies are hardly sequels to one another

@angelkr said:

Hey bylineker. I can see your point, however there's this collection https://www.themoviedb.org/collection/140760-final-fantasy-vii-collection?language=en-US where the movies are hardly sequels to one another

I think those fall into the following exception:

Series of stand-alone films and mixed series marketed as proper sequels are also allowed as collections.

So if the three movies you wanted to add had been named Sympathy for Mr Vengeance 1, Sympathy for Mr Vengeance 2 and Sympathy for Mr Vengeance 3 it would have been a fit.