Mini Ninjas ESRB summary - prepare for farting bosses

Rating summary: This is an action adventure game in which players control a small ninja as he explores forest environments, fetches items for others, and fights samurai enemies. The main character uses a sword to attack and defeat enemies, and there are occasional boss battles that use life meters to measure damage inflicted. One boss character attacks with flatulence, using fans to wave green gas clouds towards the player. - ESRB

Let me just get this straight…is it the cartoon violence or farting that earns this game its E10+ rating?

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