Stages in DSS come from many IPs, but none of XiconExertoroyah's series of his are in it except for DSS itself. For Stages, there are three kinds: Main, DSS, and Gift. Each have two formats: Basic and Complex. Basic is a simple floor, a simple background, and possibly platforms. Complex is more terrain and sprites being used. Some stages can be half and half.
These Stages come from IPs. Just like Characters, these Stages will have representation in a similar way.
These Stages are based on the lore of DSS.