Katekyo Hitman Reborn!becomes an action series. This is not clear from the beginning. And the main character is still fighting with a pair of woolen mittens secreted by a shapeshifting chameleon long after the series stumbled into Serious Business territory. Magical pacifiers are also involved in the plot and are not played for laughs either.
Not to mention that the Italian mafia apparently hires magical baby hitmen to go train their future boss. Or that it's a common staple for mafia bosses to be able to fly around shooting flames out of their hands and save the world. Yeah.