Walls writing

The  is the unofficial name given to one of the two known writings existent in the universe of the Attack on Titan manga, along with the Titan Writing. It is the writing used by the inhabitants of the Walls, appearing on a high variety of items, as well as in the inside covers of the manga.

Description
At first glance, the Walls Writing may look like unintelligible gibberish, although it is actually Japanese katakana turned upside down and messily written to make it difficult to read. By turning the text 180 degrees and some effort in the interpretation of the kanji, the writing can be directly translated to Japanese.

Appearances

 * A newspaper that Armin was reading.
 * Bottles of Titan Serum.
 * While other appearances of the Walls Writing are Easter eggs or jokes, these appearances of the writing arguably provide legitimate information about the Titan serums.
 * A book that Frieda was reading to Historia.
 * A signboard of the tavern where Levi and Kenny were fighting.
 * The inside covers of all manga volumes.