Conversation so far:
What kicked off MC Hammer's career?
Burrell formed a Christian rap music group with CCM's Jon Gibson (or "J.G.") called Holy Ghost Boys.
Was this well received?
This was Contemporary Christian music's first rap hit ever.
Who else did he collaborate with?
Via his record labels such as Bust It Records, Oaktown Records and FullBlast, Hammer has introduced, signed and produced new talent.
What new talent has he introduced?
Oaktown's 3.5.7, Ho Frat Hoo!, the vocal quintet Special Generation.
How were they received?
CANNOTANSWER.

Question: What did he do in entertainment other than music?
Self-contained rewrite: What did MC Hammer do in entertainment other than music?