Calcifer sits next to 4 phonetic neighbors — Lucifer, Caleb, and Calixto are the closest matches by sound. Most share Calcifer's English-origin cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"fire bearer, heat carrier"
"ruler, one who rules"
"one who speaks for God"
"wide meadow, wide island"
"strong lord"
"colt settlement; farm where young horses are kept"
"gaming character: adventurous young explorer"
"luxury, abundance"
"son of Ryer, from the rye field settlement"
"famous in the land, renowned territory"
"his peace"
"just, righteous, fair"
"he will judge"
"rocky land"
"young wolf, wolf cub"
"glory in battle"
"God has heard"
"warrior, slayer"
Similar sound: These names share phonetic patterns with Calcifer — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Latin (calor/calx + fer) origins, giving them the same cultural heritage as Calcifer.
Rhythm: Calcifer is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.