Re: What we know so far - T:TDW edition (no speculation, facts only)
The crew filmed about one week on location in Iceland, but details of the shoot are scarce. We know from Twitter reports that Triple A was on hand for at least some of the scenes, but we don't know whether it was as Algrim or as his alter ego Kurse.
Also, Loki participated in a large-scale battle during the Iceland filming. It's not known who was fighting whom, or which side Loki was on.
THE COTTON AVENGERS
...They move like slick cotton on oil.