Lumpy has violet skin. He has five purple hair tufts on his head. He has four legs with two small purple nails on each. He has a purple puffy tail on his back. His ears are big with the inside part pink. He has two small black eyes. Finally, he has a small proboscis with a large nostril at the end of it.
Due to Lumpy's playful attitude, Pooh and his pals learn that heffalumps are not predators, heffalumps are animals and they are herbivores. Lumpy likes honey, can be afraid at times, and loves to bounce.
Lumpy was introduced in the film Pooh's Heffalump Movie when Roo joined the heffalump-hunting expedition without his mom's knowledge, and ended up discovering Lumpy and captured him. Roo soon discovered that none of the scary things Pooh and the others had told him about heffalumps were true. The two became fast friends and were seen celebrating their friendship in the song "Shoulder to Shoulder," in which Lumpy finally "uncaptured" himself.
When Lumpy and Roo went to meet the gang, everyone (except Kanga) thought he was a dangerous monster (despite being clearly harmless) and trapped him in a cage. When the gang leaves, Roo goes back and frees Lumpy. Pooh and the others then capture Lumpy again and trap him in a net. Lumpy starts crying, but Pooh and his friends don't care, their prejudice against Lumpy blinds them from his feelings. Roo starts to tell them that Lumpy's not dangerous after all and the gang realizes what they have done. Pooh, Rabbit, Tigger, and Piglet free Lumpy and apologize for everything.
Just then, Roo is trapped under some wood. Lumpy calls for his mother and with her help, the gang frees Roo. Lumpy and Roo decide to continue playing for the rest of the day.
Lumpy joins Roo, Tigger, Piglet, Rabbit, Pooh, and Eeyore during Halloween. But when Pooh eats all the candy, Roo and Lumpy go look for a monster Tigger talked about. "'Cause if you catch it, you could make a wish!" Lumpy gets trapped in a tree and Roo later finds a pumpkin in the woods. The gang thinks that Lumpy turned into a pumpkin. But when Roo wishes Lumpy back, Lumpy gets out of the trap. And it appears that Kanga lost her own Lumpy-looking pumpkin earlier.
Lumpy's primary purpose in the Winnie the Pooh universe is to be the perfect foil for past heffalump and even woozle depictions. Heff Heffalump from The New Adventures is undoubtedly a honey thief who does not consider the feelings of others, much like his partner, Stan the Woozle. They support the original idea that all heffalumps are like this. Lumpy's significance comes in the form of proving to the occupants of the Hundred Acre Wood that not all heffalumps are this way and are capable of making good choices and building good relationships and the anti-racism message of the movie.