Kadokawa Games announced the Kadokawa Games Dai Kanshasai 2019/Big Thanksgiving 2019 event, which will be held on October 19, at the Japan Education Center in Chiyoda, Tokyo. Kadokawa Games confirmed the event will reveal new information on upcoming games for the Metal Max series, celebrating its 28th anniversary, and on Kadokawa Games' Mystery Series, which includes Root Letter and its upcoming sequel Root Letter 2. Announcements regarding other games will be revealed as well. As such, it's highly possible we'll see news regarding God Wars 2. We should see news regarding mecha RPGs Project Europa and Project Stella as well.

The Kadokawa Games Big Thanksgiving Event will also include a concert by Iris, who will sing the theme song of the next Mystery Series game, Root Letter 2, revealing the song for the first time. Multiple live events with voice actors and Kadokawa Games developers will be held. A giant rock-paper-scissors competition will be held as well, and exclusive goods will be sold at the venue.

Kadokawa Games organizes this event each year, but it's usually simply called the "Kadokawa Games Dai Kanshasai".The fact that they're adding "big" in the title for the 2019 edition further hints at big announcements coming.

No platforms have been announced yet for the next Metal Max game, God Wars 2 and Root Letter 2, meaning we should learn more about that at the event as well.

Metal Max Xeno Director Hiroshi Miyaoka and Producer Juntaro Kouno recently teased that a new Metal Max game is in development and how an official announcement would be coming soon. The last game in the series is Metal Max Xeno.

Kadokawa Games announced Root Letter 2 back in 2018, along with Root Letter: Last Answer, which is releasing on September 3 on PS4 and Switch in the west. A Hollywood adaptation of Root Letter is also in production.

Iris member Yuu Serizawa teased back in 2018 she is involved in God Wars 2.

Iris is an "idol seiyuu" group, with the 6 members regularly voicing anime characters. Iris reached peak popularity by regularly voicing characters in the Pretty Series idol franchise by Takara Tomy, which contains Pretty Rhythm, King of Prism, PriPara and Kiratto Pri Chan. Yuu Serizawa most notably voiced the character Ann Fukuhara in Pretty Rhythm Rainbow Live. All six Iris members voiced the six main character in PriPara, and three members of Iris are currently voicing three of the main characters in Kiratto Pri Chan.

Taking this into consideration, it's very likely Iris members will be voicing characters in Root Letter 2 or other upcoming Kadokawa Games works rather than simply singing a theme song.