Action Set Triggered by Stage Move

Is having an action set linked to a stage movement (without inserting inside a sequence) a legacy feature?

This was in place before I set-up stuff inside this account. actionsetlegacy

It’s an action to take when a stage is moved, not to be confused with the actual moving of the stage. ie stage moves are only a manual process. So when someone edits an opportunity and moves the stage to another, and then clicks save, that action set will run if it’s tied to the stage that someone moved the opportunity to.

I’m also curious on how to do this. I want to run an action set when a custom field value is updated