Unknown writing

The unknown writing is one of the two known writings existent in the universe of the Attack on Titan manga, along with the Walls writing. It is a mysterious writing that so far only Ymir has been confirmed to be able to read.

Description
The unknown writing is very similar to the Walls writing, although it is known to be a different language since none of the Survey Corps members (seemingly including Reiner, a warrior from Marley) present at Utgard Castle were able to understand it; with the only exception of Ymir. The reason why she can read the writing is still unknown.

Appearances
The existence of the unknown writing is revealed when a small group of Survey Corps members (including graduates of the 104th Training Corps) take shelter at Utgard Castle and find several mysterious crates left recently by unknown occupants. They discover that the crates are full of supplies labeled in a strange language they can not understand. However, Ymir inadvertently reveals to Reiner that she is able to read the writing when she reads the label of a can of herring.

Trivia

 * Page_of_Ilse's_notebook.png Although the writing on the wine bottle is simple gibberish, the writing on the can of herring is Japanese katakana turned upside down and slightly altered to make its reading difficult and give the impression that it is a different language; similar to the Walls writing. However, unlike the Walls writing which is read left to right (like regular Japanese), the writing on the herring can is read right to left.
 * Eren_in_Titan_form_remembers_his_father's_fate.png Another case of writing in a similar style as the one on the herring can is found in Ilse Langnar's notebook. In one of the panels it can be seen that the text she is writing is katakana turned upside down and right to left. While this has not been officially addressed, this is most likely an inconsistency on the part of Hajime Isayama's assistants rather than a connection between Ilse and the goods at Utgard Castle.
 * During Hange Zoë's experiments to Eren Yeager in Titan form, Eren is depicted writing "ate" (クッタ) in a style that matches that of the herring can writing. According to Hange, he had written messages saying that he could not figure out how to harden his Titan form, followed by "What my father did to me". The katakana he is writing, if translated directly, seems to refer to how he was forced to eat his father. This has also not been officially addressed, and is most likely an additional inconsistency on the part of Isayama's assistants.