finding uses for the inventions, and relying more on intuition than knowledge. He also appears to have slightly better social skills than Mud. Slinger's skin is green and his facial features are more angular. It was once revealed that he has by far the best sense of smell in the marsh. Both have troll-like appearances, with large furry ears and bright blue except on their faces and hands. Mud/Slinger is the strongest Groundling in the marsh and is always creating inventions out of the junk that humans throw away. Often, these inventions malfunction. Sometime in the past, Mud and Slinger's Grandcestors (the Groundlings' term for ancient ancestors) named Slide and Mash both lived all alone in a part of the marsh and had no friends. After meeting each other and forming a deep friendship, they wanted to be merged as one, for fear of ever being lonely again. Unseen spirit creatures called the Tree Elders gave them a potion that did just that. Since then they lived happily. This implies that all of Slide/Mash's descendants, including Mud/Slinger, have been conjoined twins. Mud/Slinger occasionally quarrel, but solve their differences easily enough. In the episode "Two Be of Not to Be" after Hegdish causes a major disagreement between Mud and Slinger, they decide to take the same potion, which will give them separate selves. But before they can go through with it, they learn Slide/Mash's story and that the potion only works once on every pair. Thus, they resolve their quarrel and renew their friendship. They share a catchphrase at each other, "Did Not and Did Too!" The malfunctioning inventions combined with occasional disagreements, makes Mud/Slinger the series' comic relief. But despite causing problems accidentally, Mud/Slinger is generally beneficial to the marsh and a help to his fellow Groundlings. Stacks Stacks (performed by James Rankin) is a large robot built by Galileo out of junk that humans have brought to the marsh and brought to life by a powerful lightning storm. He eventually becomes a mobile unit when his essential components are placed in a special motorized vehicle (which Mud/Slinger created for him using an old shopping cart) and for which he is very grateful (though gets carried away at first). Mostly, he is humble and kind, and tries to answer the Groudling's questions with information from his database. He sometimes feels insignificant being "just a machine" (as in the season one