Challenge Me!!!
Como se dice en espanol: Challenge Me!!!
and also: Show me what you got!!!
I also want it to come across in a playful way.
3 Answers
Challenge me = rétame
A literal 'show me what you've got' = enséñame lo que tienes. - which I have heard but there's probably a better colloquial version.

What's the context of the "Challenge me!!!" part?
Show me what you got!! --- "¡A ver! ¿Que traes tú??!" "¡'amonos!"
Your facial expression and tone will be the biggest way to communicate it playfully or not.
¿Que traes tú?
This is what we say in an accusatory manner for: What´s your problem?
'show me what you've got'
For this we would normally say: A ver ¿qué tienes?