The ‘Pac Man Frog’ is a name given to the Amazon Horned Frog, which is described in the article linked to below. This frog will eat almost anything smaller than itself and then some (or at least try and eat some things bigger than itself).
Being the size that it is, it is hard to believe that Saolas are rarely seen. Not only is it rarely seen, but the Saola was only discovered in 1992. The Saola is best described as a large antelope-like creature.
The Saola lives in the mountains of the Laos and Vietnam border region.
One of these rare Saolas was captured by Laotian villagers in August 2010 and sadly died in captivity.