Water spirit introduction! It's the first spirit we see being aligned with the Ice Kingdom; it makes me wonder if the water spirit is doing this out of free will.
Otr is in the mind world to talk to Fylgja. I never quite understood why Fylgja disappeared, though that's probably just my reading comprehension skills being lacking. With the attack on the World Tree, I wouldn't be surprised if Otr has an Avatar state interrupted moment.
We're going through arcs at a breakneck speed right now. Hopefully this isn't an axe sign. Even if it isn't, I genuinely don't see how Otr can recover from this; we're 25 chapters in, and we have already covered 5 spirits... There are also some weird inconsistencies this chapter as well. For example, Khuteinn just appeared at the elven secret ritual place, even though he wasn't here last chapter. Also, where's Etupirko and Huginn? Hopefully this is intentional, and Kawaguchi-sensei isn't doing it to force character moments into the manga early before Otr gets axed.