There will be an additional update to arena that will allow you to use ninjas. On the china server, you have ranked/training in one page and the non-main arena in another.

non main area is a good idea. any reason we can't just pick the ninja we want to be at the start of the game.

I guess main is supposed to be your identity even though there is no character customization outside of clothes. Only thing I could think is that the main lets the other player know which ninja to take down if they want to get rid of the chase summon. Unless you'd be willing to not have a chase summon with your team that has no main.

well you dot need the main to chase is the probably. I was fire for the longest and hes was dead weight half the time that got shutdown by masked man leaving my whole team to be killed before round 2 even started. That and again I like using gimmick teams or teams of my making so being force to have a mandatory ninja I dont want or merely provides passive healing and maybe some control is a waste even if i can get 3 extra attacks via chase and summon. an before some says that maybe the solution is I should change mains I did and thats were the the problem is the fact that I have to change a mandatory character to a set setting is what irks me how can I make whatever team comp I want in something while others I can not.

your main also has more skills than normal ninjas

main is meant to be there as a support for other ninjas, other ninjas can't change passives and chases as they like, main can.