A hardcore game can be anything that isn't a family/party game. So yes, games like Super Mario Bros., Pikmin and Donkey Kong are all hardcore games. A game doesn't have to have a lot of blood and violence to be hardcore, it just has to be a game that takes a lot of skill, is really challenging and isn't just a one-time thing.
So if you aren't into the games that you mentioned, that doesn't mean you don't like hardcore games. It just means you aren't into those sorts of games.
Anyways, I'm sure there'll be some casual games on the Wii U like Wii U sports and Wii U play.
- Feld0, Guest, Hardcore Brawler and 1 other like this