Great job, Alvin. Very thorough additions!
What does the article (or section) do well?
Very detailed, good explanations, unbiased.
What changes would you suggest overall?
Create a more defined hierarchy of headings. General info and Frequently used terms should definitely stand out more than Prestiging Allied Gyms or Destroying Enemy Gyms.
Additional photos/citations would also help to bring your additions to the next level. Overall, awesome contributions!