Some info about the similarities:
https://ad.gamersky.info/@steamcommunity.com/app/385380/discussions/5/601889972151196809/

gonna repeat what i said on a similar thread
Planet Centauri is NOT a terraria clone, not even the building mode of the game is similar to terraria
Planet Centauri focus in a sandbox souls-like and metroidvania
when i say "focus" i mean by customization, you can literally make your own customs spells for example, you can tame any monster (except bosses) of the game, can enchant your weapons and armor in various ways and the list is extensive