The Dull Bones appeared in 2004 videogame called Paper Mario: The Thousand-Year Door. The Dull Bones are variants of Dry Bones found in the Paper Mario series. In Paper Mario: The Thousand-Year Door, they appear commonly in Hooktail Castle. In this game, they are weaker than Dry Bones. Dull Bones attack by throwing bones at Mario and his partners. Despite having very low HP, their defense power makes them slightly harder to defeat. Despite this, they are easily taken out by simply using the Hammer. Using a POW Block or Koops’s Power Shell is also very efficient, especially when there are many Dull Bones in battle. Unlike Dry Bones, they cannot reassemble once they are smashed. However, Dull Bones can construct other Dull Bones to help in the fight. Three of them appear in the Glitz Pit called the Dead Bones. One is also in the Riddle Tower as the weakest Dry Bones-esque enemy, which must be defeated first. They also appear in the first ten floors of the Pit of 100 Trials.
Dull Bones and Dark Dull Bones also appear in Super Paper Mario. Dull Bones can be found in The Underwhere, Castle Bleck and in the Flipside Pit of 100 Trials. Unlike Dry Bones, however, Dull Bones can also throw bones. They are also very weak against Bowser's Fire Breath. They are much stronger in this game and actually stronger than Dry Bones, compare to how they were in the predecessor.
Several Dull Bones make a cameo appearance in the Nintendo Monopoly board game.