What's your favorite frog or amphibian themed module and monsters? why?

[TBeholder]

"Kuo-toa are an ancient race of fish-men..."

 

[Grogg of the North]

In the 3.5 monster manual they appear more frog like to me. And their description only mentions that they are amphibious. So I guess I qualify for the amphibious part. My apologies for any confusion.