Thanks to the Most Wanted Commander Deck, Outlaws go hand in hand with Treasure generation, and Prosper is one of the best of the bunch in that area
This card is crucial for decks like Raging Bolt ex, as it can search the deck for every Pokmon in the deck and help get their plays started very early in a match
You can cast Failure to bounce a spell and then Comply naming the spell, and your opponent can't cast it on their next turn, but Reflector Mage (an uncommon itself upgraded from common thanks to the "can't cast" clause) comes along with a very blinkable and close to on-curve body, which makes it much, much better than Failure // Comply
I like it in decks that want to discard with Mask of Memory and other effects, too
The man was reported to have been stopped by officers who then discovered the undeclared Pokmon cards during a routine check, leading to his current predicament
However, Kozilek is also a powerhouse of a control card