Quoted By:
Of the new Bionicle sets (released in 2015) - best to get Tahu (2015 version with the lava boards). He's the most complete looking and was pushed hard as the lead.
But it also depends on who you're buying for - what they like etc. If they prefer the white/ice design, Kopaka 2015 would also be fine. The toa (the hero characters; tahu, kopaka, onua, gali, lewa, pohatu) would be a better choice rather than the villians(all the skull things you mentioned) as they are more iconic of what Bionicle is
