Common Sense Note
Parents need to know that this is a violent cartoon double-feature of long short subjects (or short features) featuring Marvel comics characters, not a live-action epic. It presumes the viewer has in-depth knowledge of the Marvel Universe; newcomers to Hulk and X-Men stories will be especially puzzled. The combat, especially in "Hulk Vs. Wolverine," is unusually vicious for a "mere" cartoon. Red blood pours (even from the green-skinned Hulk, strangely), and arms are torn or amputated off. Wolverine and a few other characters are depicted as heavy drinkers. Deeply religious families may be put off by the pantheon of pagan gods and magic of "Hulk Vs. Thor" (even though it's clearly set in another world).
Busty cartoon superheroines have supercleavage-revealing costumes.
Brutish combat in both episodes, including bloody, broken superhero bodies (which can be magically or technologically healed straightaway though, or something). The "Hulk Vs. Wolverine" segments feature stabbings and blood spurting and limbs ripped or cut off villains by the Hulk or Wolverine - with the qualifier that the torn-off body parts are (usually) cyborg and can be reattached. Painful-looking creature transformations and declarations that actual death has occurred (even though Marvel stories are notorious for arbitrary resurrections).
Some "damns," a very literal reference to hell, and an incomplete "stick it up your...!"
Though nobody ever seems to notice it, the seemingly all-destructive Hulk protects innocents from harm, at least when part of him is the Dr. Jekyll-like figure of Bruce Banner. There is the theme of self-sacrifice in the "Thor" episode when Banner gives up his brief, heaven-like afterlife existence to join with the savage Hulk and cease the monster's unstoppable rampage. The "Wolverine" episode, meanwhile, is largely a free-for-all in which violence solves (or doesn't solve) everything, and even public troubleshooter Wolverine has his unsavory attributes.
Tie-in to vast quantities of related merchandise.
Drugs / Tobacco /
Wolverine and one of the Thor's fellow warriors are both heavy drinkers.