Hello!

The Test Ninjas are basically meant for beginners who don't have any viable ninjas yet. They can hire a ninja for a few days that they c*e with their dailies and other events of the game. As for the other ninjas or updates to add more ninjas in there, I have no information yet but it is worth a try to ask my superiors for it. Thank you.

I'm surprised they don't make more use of the test ninja myself. If you ever go into sales they first thing they tell you to do is get the customer to hold the item. Why you ask? Because its about possession and ownership once they have they are reluctant to give it up. So putting in more ninja that are currently in events would in theory increase purchases for those ninja.