Hero sits next to 4 phonetic neighbors — Nero, Zero, and Arrow are the closest matches by sound. Most share Hero's Greek-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"defender, protector, warrior"
"ancestor descendant"
"Wise one, a sage person"
"friend of God, beloved by God"
"son"
"path, narrow lane"
"powerful army"
"dark as a raven"
"peace and agreement"
"from Laurentum; laurel-crowned"
"initial-name, typically Andrew James or Anthony John"
"speckled, variegated"
"a crow-like black bird"
"secluded valley"
"third son"
"the wild cat"
"lord, elder"
"possible Japanese aesthetic: figure, image"
"son of Colin"
"deer meadow"
"eastern town"
Similar sound: These names share phonetic patterns with Hero — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Greek origins, giving them the same cultural heritage as Hero.
Rhythm: Hero is a 2-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.