There really aren't any rules for Annuals, just think of them as birthday issues for your favorite title.
They CAN be part of the month to month continuity, but they don't have to be.
I've even seen annuals that have their own continuity with other annuals. If it's part of a larger continuity, that will usually be noted on the cover.
For example:
They can be by the same creative team as the monthly book, but again, they don't have to be.
Sometimes annuals serve as try-out books for new writers and artists to see how they handle a property.
Image posts are not allowed, see [email protected] and [email protected]