Atlus has decided to tease Etrian Odyssey fans with something new, and the kicker to all of it is that we don't know what it is yet. There are already going to be a lot of eyes on the series this week as Etrian Odyssey X will be released on the 3DS, so it appears that the company decided to capitalize on this and revealed a brand new trailer that looks like a new game is on the way.
As you can see from this video, you get a look at several graves, followed by silhouettes of characters, and then a look at a lit forest. If you're curious about the wording, several fans online have already pointed out that translates it stands for "SQ, fetal movement" followed by the text "to the next stage." According to a few different posts on Twitter, the SQ is a contraction of "Sekai no Meikyuu," which was the original name for the series.
Beyond that and some hints on the official Twitter account for the series, there's no info out there about what kind of game this could be. Will we be getting a sequel on a console, or a mobile app game? It's up to Atlus to tell us at this point.