Attack on Titan manga receives an additional Volume - What is Isayama cooking?

Attack on Titan manga will have brand new content with an additional volume to the manga. Here's a guess what Isayama might be up to

Attack on Titan 20 by Isayama, Hajime

Attack on Titan 20 by Isayama, Hajime

A Village in the Mountains — Shingeki no Kyojin Fake Volume Previews and Extra

Attack on Titan Season 1 Part 1 Manga Box Set by HAJIME ISAYAMA - Penguin Books New Zealand

Lot Of 12 Attack On Titan Manga Paperback Books By Hajime Isayama

Attack on Titan manga receives an additional Volume - What is Isayama cooking?

Attack On Titan to Get A Bonus Manga Chapter - Good e-Reader

Attack On Titan 1 - By Hajime Isayama (paperback) : Target

Pre owned, good condition. A few pages have yellow ink, shown in pics. Please check out the pics for details.

ATTACK ON TITAN Manga Volume #1 By Hajime Isayama- English

Attack on Titan manga receives an additional Volume - What is Isayama cooking?

Attack on Titan, Vol. 14 by Hajime Isayama