Everything will come from this official blueprint given by splunk:
https://www.splunk.com/pdfs/training/Splunk-Test-Blueprint-Power-User-v.1.1.pdf
So just read/practice whatever topics mentioned in the blueprint and then you are good to go.
ALL THE BEST !
most certainly not - Splunk Certification exams are not open‑note. This means that any reference material (notes,
course documentation, access to Splunk Docs or Splunk Answers, etc.) is strictly prohibited. Both
on‑site and online proctors are trained to identify unauthorized materials or behavior. Any
perceived violation of the closedbook policy will result in automatic failure and forfeiture of
registration fees.
Ref https://www.splunk.com/pdfs/training/Splunk-Certification-Handbook-v.8.31.2018.pdf
Always go by the official product guidelines 🙂 🙂