hard core [hahrd-kawr]
noun
1. The permanent, dedicated, and completely faithful nucleus of a group or movement, as of a political party.
2. An unyielding or intransigent element in a social or organizational structure, as that part of a group consisting of longtime adherents or those resistant to change.
3. Those whose condition seems to be without hope of remedy or change.
adjective
4. Unswervingly committed; uncompromising; dedicated.
5. Pruriently explicit; graphically depicted.
6. Being so without apparent change or remedy; chronic.
EX. Note to self; if need be, use a time machine to go back in time and prevent the creation of the hard core Captain Planet and the Planeteers by the same decade that brought us Rob Liefeld's abominations, Todd McFarlane's Spawn and the Spider Man Clone Saga.