Project Orion (or SpigotCourse back then) is a really powerful course that covers plenty of topics, ranging from simple commands/listeners to the detailed usage of APIs (for NPCs, particles, and more). These topics are, without a doubt, beneficial to every programmer in the field of plugin development. Although I personally didn’t prefer using it, the course contained a utility resource to help those interested in premade methods for inventories/items/conversations/et cetera. It helped with more than just plugin development by focusing on general topics for development and developers that help with scalability, marketing, security, and more. Overall, it is a pretty good and resourceful course for any developer even those with experience I am sure there will always be something new to learn.