The Bear is a major character in the episode "In Your Footsteps." After Finn saves it from choking, the Bear follows him and Jake to the Tree Fort. It tries to copy Finn because it wants to be a hero. Finn gives him the Enchiridion instead, which the bear later gives to the Lich-possessed Snail.
He looks exactly like a normal bear with brown fur. At one point, he wears Finn's clothes and a poorly made mask that is supposed to resemble Finn's face. He can talk or mimic talking and can write, but he writes the letter "S" backward and is not a good speller.
He has demonstrated a calm personality and not a very high intelligence, believing that by copying Finn, he would automatically become a hero. However, it is unclear whether this is his true nature, due to his connection to the Lich, as he could have concealed an evil personality or even been deceived, since his attitude apparently does not change when he encounters the Lich.