it's a game you can play like jeopardy where you are presented with the "answer" or punchline to a joke and are asked to come up with the "question" or a statement that otherwise would elicit that punchline.
"Want to play joke jeopardy?"
punchline: to get to the other side.
setup: Why did the chicken cross the road?
punchline: the gooey-decimal system.
setup: How are porno stores organized?
Batmanning a ho entails a surprise entry into the "batcave" followed by a load of skeet to chest (to symbolize the batman logo) while saying "bam, kersplat, pow, etc..." as an omage to the Adam West Batman.