inflexible vs hard-core

inflexible and hard-core both are adjectives.

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

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