2015 drawings of the characters were used as a refrence in a majority of G2 media.
Having a 2015 version of the character cannot be used to determine when the art was made or for what year.
- 2015 Toa were used in the images of the maze
- The 2015 Tahu debate when he appeared on the box art of a 2016 summer set
- multiple other examples in media
#The artbook is definitely not in order.
*Or at least the villains definitely are not in order
Shadow traps concept art before and after 2015 Skull villains
Umarak concept art before and after 2015 Skull Villains
Beast concept art before and after 2015 Skull Villains
Please check sources before dismissing things
The reason why i feel it is a 2017 villain concept art;
Transparent bones, which were a primary feature of all the ‘demonic’ villains shown in the art book, the gimmick is different
Waist Swivvel piece, introduced in Winter 2016 and unlikely to show up in concept art from 2013/14 in such a detailed way
Upper leg armour piece, introduced in Summer 2016’s Star Wars line
Background is similar to the demonic background we see ‘Demon Warrior’ along with matching the background of the Toa during the 2017 Summer teaser image where they go to confront Makuta in the shadow realm
The issue is that other than the similarities to the Skull Villains, there isnt really anything that can be used to dismiss this as not a 2017 set at this current moment. I suppose the similarities to Demon Warrior, who was shown in the 2015 Villain concept art could potentially mean he was one of the rejected 2015 villain designs, but we have’nt really had anything concrete yet to confirm it.