OK, here's my wild stab in the dark about the new sets. I think the names shown are not going to be the final names of the sets. Two things clue me into this, the "Mask Maker" set isn't referred to a Ekimu (I'm going to assume that the set is Ekimu until proven otherwise), and the names of the other sets are very similar to the “in progress” name of the LOSS (Skull Krana). As for the possible identity of the sets, I think that these are going to be a redo of the infected rahi from Gen1 Bionicle with the Skull Spiders playing the part of the infected masks.