Blue Mailbox functions the same way as a regular mailbox, letting other players place private messages in it using the Wrench. Unlike the mailbox, it is a solid tile.When a letter is put in then there are a lot of letters stuffed in a mailbox. The blue mailbox once had a bug where when a letter was put in it, it would turn into an Arid Weather Machine but the weather machine would act like a mailbox instead of a weather machine.