Well, the term "hard core" can go a lot of different ways. If by hard core you mean THD games or basically games that show off your tab's graphical prowess... you've got most of the top ones already. There are some nice older titles like Roboto HD that look great as well but aren't graphically as strong as games like Shadowgun or 9mm.
If you want games that look good and actually work like they're supposed to the ones I added are nice options; It really just depends on the type of games your looking for. I generally blow through 40-60 games a week and can put any others I find in the thread bsweetness suggested, thanks for that btw there were some there I haven't tried yet.
I picked up my tab 2 days after it dropped on-line, and my biggest gripe so far besides color depth has been lack of compatible games. There are a lot out there, but I was surprised at how many don't play nice with ICS or with tablets in general.
They like to tout the "power of gaming" with quad-core devices, but they don't talk about the lack of quality or compatible games do they...