S7 Senpai Reign here giving you guys the inside scoop on how to get top ranks during nine tails events.
This seems to somehow not be common knowledge despite me sharing it over and over on my own server but the current best setup to handle nine tails is running 10 hit chase ninja together.
Fires are the most dominant class in the game and this will remain so especially after 55. So if your a fire ninja congratulations! getting rank 1-3 in nine tails even will be super easy for you because you can run an optimized 10 hit combo team and buff it with your passive.
Begginners line up- This is for low levels who might not have much unlocked yet but the key ninja is Iruka.... If you passed up the recharge even to get him then you're gonna be missing a large damage boost for free but don't worry you can still keep up without him.
For new players I suggest something along the lines of Kiba/Sasuke/Ten/ten or Karin ( most people get Karin from free seals tbh ). For Fires you want to make sure your using your multi hit attack and buffing your Fire damage with your passive. if You are level 50 you want to use your 10 hit chase summons ( ton ton, chameleon, king of hell, guys turtle ). if you are fire and over 55 you want to make sure you use your oboro clone it does fire elemental dmg which will always trigger double dmg on the fox.
For those not fire use the mindset that you basically have 4 rounds to do as much damage to the fox before he bombs you. You want to prioritize doing as much damage as possible in those 4 rounds since the fox will generally not kill any of your guys until he bombs you ( if you are reallllyy low level this is why we use kiba to have his clone soak up the early damage since you are still low level and squishy ). The key for consistant damage is ninjutsu damage or any attacks infused with an element. Elemental damage always does bonus damage to the fox since he is every element and will always be weak to something. This is why I prefer Karin in my composition over Ten/ten ( unless you have great ninja war ten/ten which is obviously way better choice than karin ).
Advanced lineup- So this lineup is why Fire MC's will always win nine tails ( unless you have a vietnamese gold botter in your server like we do who's spent 5,000 dollars already in the game and is 10000 power ahead of everyone else ) and you'll be the envy of your server!
With the current limitation of ninja in the game what I have found works the best so far is Anko,Iruka,Karin. The reason for Anko is the Fire domain she puts up with her ability. it's a straight 40% dmg buff to your team and it doesn't interfere with any of your Jutsu timings. Everything lines up just right and the key is to keep her domain up as long as possible and not to use her secondary ability to attack. You lose a 10 hit combo but make up for it with a straight 40% damage buff that after testing has seem to netted the best results until we start getting some wind blade asumas and other things into the mix. When I ran this setup even being 2-3k power below the other top ranks I still managed consistant nine tails rank 1s. After I started using this composition it became the norm on the server and we basically kill the fox in under 10 minutes now. Until new characters come out or people get access to the better options in the seals this seems to be #1 way to go for the most part.
Now for those who are not Fire well your options are a little different and while I haven't had time to experiment my suggestion for you is still 10 hit chase ninja. For lightning maybe run sasuke and use him like you would anko for the lightning field bonus. If you are not Fire main I highly suggest using ten-ten however, she will make up for lot of damage you lose to the Fire Buff.
Later on-
Later on I feel wind blade asuma iruka and a combination of another ninja ( not sure who would work best yet ) will be the better option. Wind Blade asuma gives you massive dmg boosts as long as your full hp which you will be with iruka sheild and since you'll probably be higher level anyway. The game has many options for compositions it's just unfortunate majority of the better characters are locked behind massive paywalls. ( Shame on you Bandai ).
These are just the things we have done on our server and they seem to work. This might not even be the best thing to do and we just haven't figured out the right setup yet but it's whats consistantly getting me rank 1 on our server and getting my group mates into top 10 even without jonin medal benefits. Hopefully it helps some of you because I'm sick of answering questions all day when event is over.
On a side note... Jonin medals gives a 15% boost to damage and you should always save your coupons for nine tails to use to revive and max out all your attributes with kage/anbu support. Nine tails will be a large portion of your money income in the higher levels and exp gains. Once your in the later 50's and 60's EXP becomes painfully slow. Nine tails if you kill it will net you about 1 million coins and 450k exp for rank 1. The server needs to work together to kill it because it's worth it. Not killing it is never worth.