Problem
On Episode 6 of the Spelunky Showlike podcast, "Making Spelunky 2 with Derek Yu," at approximately 1:23:26, the indie game designer recalled a simple request by his daughter:

"I think her one major idea that she had was that she wanted to add an octopus arm that you could get, and she was very insistent that the octopus arm was used to destroy the ghost."

Unfortunately, although Derek notes that it is "a pretty cool idea," he predicts that it will not make it into the final game.

Solution
Derek Yu (or a sneaky employee at BlitWorks) adds an octopus arm that can be used to destroy the ghost in Spelunky 2.

Personal story
I am a young boy who speedruns Spelunky and, like Derek Yu's daughter, I dream of destroying the ghost with an octopus arm.

-ix