I am aware of this, but if you have a look at Sage Naruto Treasure you will see Sasori[100 Puppets] has a purple colour around him, not a gold. This indication he is just a rare. But as we all know Sasori[100 Puppets] is not a rare but a Super Rare requiring 400 Seal Scrolls to pull.

The 3 Sannins have a blue colour around them, this indications they are common ninja not rare(Only requiring 10 Seal Scrolls to pull) :)

The Ninja Preview also don't tell you all Ninja's you can acquire e.g in Seal Treasure you have a chance to get Elder Chiyo,Guy,Jiraiya,Kakashi,Ororchimaru,Shizune or Tsunade from a 10 Pull. But the Ninja Preview doesn't show this.

The main purpose of this post is to not only see if Konan and Elder Chiyo[Chikamatsu of Ten Puppets] are really only rares but also work out what other ninjas outside the Ninja Preview can be acquired.