Wait does she? I thought it was only wolf Grimm, unless I’m misremembering. She does kill a whole lot of them though.

I think you're thinking of the Red Trailer -- I'm talking about the V4 Character Short. I don't blame you if you never saw any of the Character shorts leading into V4, 5, and 6, they weren't very well advertised or integrated. I myself saw the V4 character short the first time around and then never any of the others until my latest rewatch (the one that started this whole fandom dive).

This is news. I hope the animation studio can live up to Monty’s legacy, and also that whoever they put on the writing team is a better writer than Miles and Kerry.

Yeah, about that...

Apparently there was an animatic preview of some stuff for Volume 10 and Critter’s breakdown was… quite scathing.

Oh, the V9 epilogue animatic? That's basically semi-canon and was released seemingly because they thought that was it for RWBY because of RT's shutdown. It's likely that parts of that will be integrated into V10 but a lot of it will likely end up on the cutting room floor. There was a brief time where that animatic gave birth to Nora/Velvet "finding herself out" shipping, tho. TBH I don't think the animatic was awful but that might be because of the absolute tire fire that was RWBY: Beyond.

Is it confirmed for release? I thought they released the trailer and opened the shop to gauge consumer interest in an animated series, which tbf I think Homestuck has faded from popularity and publicity and is now mostly a cult classic.

TBH, I don't know. I don't keep up with these things and just assumed that they did the trailer to drive hype because they made an entire new studio for it (or like, secondary studio-thing? It's not the same Spindle Horse name). But even seeing glimpses of the Hazbin/Helluva fandom I expect there to be a lot of people (especially young people) to be checking in and following this "new Homestuck thing" animated by their favorite studio.