Board Thread:General Discussion/@comment-28013738-20170307133051/@comment-26484417-20170307152333

Since Headon is charged with the Floor where Irregulars first arrive, it makes sense that he can communicate with them. This could be either because he somehow knows their language (e.g., extracted from the Irregular upon entry), or it could be some kind of communicating ability / contract (i.e., the audience understands what Headon is saying no matter what sounds he makes, and vice versa--this could apply to all Guardians).

Even if Zahard or someone in his company taught Headon their language, the language would have evolved and changed on the Outside in who knows how many thousands of years. Not to mention that there is no guarantee--and it's in fact unlikely--that the Outside World only has one language.