Don't get me wrong - I didn't mean to say all courses on udemy are bad. I just wanted to make clear that they are in no way affiliated with Splunk, and if they claim that a course can help you pass a certain exam, it only means it covers it's contents, but it's not in any way officially recognized by Splunk.
I've enjoyed good courses on udemy (although I haven't had any on Splunk there) 😉
Getting experience is a really important part, you may also hang out here on Answers or on the Splunk Slack Usergroup, a lot can be learnt there. In addition, you could try asking the certification support, as mentioned above, if you can skip the required course for the Poweruser exam - it's worth a try, they can only say "no".
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