Some suggestive references.

Sci-fi violence and chase sequences.

Family-friendly name calling and insults.

In the episode "Return of the Crimson Binome" Captain Capacitor calls Enzos dog Frisket a "Hellhound" after freezing him in a cube.

Little to none. Implied alcohol consumption in one episode.

Hexadecimal's design may scare some viewers

Beginning with the third season, the series takes a darker turn with prominent characters dying.