hard-core vs inflexible

hard-core and inflexible both are adjectives.

Word	Noun	Adjective	Verb	Adverb
hard-core	No	Yes	No	No
inflexible	No	Yes	No	No

hard-core (adjective)	inflexible (adjective)
extremely explicit	resistant to being bent
stubbornly resistant to change or improvement	incapable of change
intensely loyal	not making concessions
	incapable of adapting or changing to meet circumstances