wow this was really impressive for being made in Scratch, good work! Art is well done, but in space invaders, the shooting is really slow and in the castle game, you can really only win if you're the archer because the melee attacks aren't very effective when the enemies attack you at short range. Also, I don't see how this relates to the theme at all. As far as a working, playable, fun game though, you did a good job given the limitation of your game engine!
I'd appreciate it if you could play/rate my game as well! :)