How to write "Guardian" in the game in English?

Guard, defend, ward, watch, and protect are verbs, such as guarding something, defending the position, watch the criminal, protect the tower, etc.

Guardian, defender, watcher, protector, and keeper are nouns, such as describing occupations, city watcher (city watcher), dragon`s guardian (dragon guardian), castle`s keeper (castle guardian) ), etc.

Guard is mostly described as security, bodyguard, guard, etc., which is synonymous with guardian, while guardian is more used in formal occasions, religious, official, and written titles. Wardens are often called wardens, principals, and guards.

Zero guardian: subzero guardian \ keeper \ protecter