Heracles vs Herakles

Heracles and Herakles both are nouns.

Word	Noun	Adjective	Verb	Adverb
Heracles	Yes	No	No	No
Herakles	Yes	No	No	No

As nouns, Heracles and Herakles are synonyms defined as:

Heracles and Herakles: (classical mythology) a hero noted for his strength; performed 12 immense labors to gain immortality

Other synonyms of Heracles include Alcides, Hercules.

Heracles (noun)	Herakles (noun)
(classical mythology) a hero noted for his strength; performed 12 immense labors to gain immortality	(classical mythology) a hero noted for his strength; performed 12 immense labors to gain immortality