epic vs epical

epic is a noun but epical is not a noun.

Word	Noun	Adjective	Verb	Adverb
epic	Yes	Yes	No	No
epical	No	Yes	No	No

As adjectives, epic and epical are synonyms defined as:

epic and epical: constituting or having to do with or suggestive of a literary epic

epic (noun)	epical (noun)
a long narrative poem telling of a hero's deeds

epic (adjective)	epical (adjective)
constituting or having to do with or suggestive of a literary epic	constituting or having to do with or suggestive of a literary epic
very imposing or impressive; surpassing the ordinary (especially in size or scale)