[TOMT]Show about a teenager ninja fights orcs/trolls on a flying ship

Pre-2018 3d animated show with a uniquely bad art style.
Only recalled scene is one where the protagonist is trying to sneak by two trolls/orcs through a vent, does something to cause a smell which prompts one of the orcs to ask another one "Did you fart?", to which the other one answers "The one who smelt it dealt it".