Id say all of the mains work.
Because if you're smart and save coupons for valuable stuff instead of just buying everything you can get really far into the game without the need of buying a medal or anything :)

For f2p, it might be fire or water. You get a lot of ninjas that you can 4 and 5 star pretty easy that works with them.
You c*so do well with Fire on 9tails with a f2p team.

maybe you need to change your question a little bit.
which main is the easiest to play if goes F2P? then i will make it simple
this is my opinion from my experience. i will start from the easiest to the hardest
Fire -> Water -> Lightning -> Earth -> Wind

about strongest lineup it depends on your own managements on many things
(events,coupons,coins,etc)

If you are asking me which character were the best, i will change your subjective question into objective question back to you.
Here is why i said so.
Let me tell you about something, no hero in this game are weak, they re all have their own abilities. Do you really read the abilities?:L
Scarlet Blaze, Azure Fang, Crimson Fist, Midnight Blade and Breeze Dancer are all good for beginner because if you re not leveling up, there's no chance for you to win even a single battle. Do you really know that leveling up no matter what kind of hero you have, can help you to beat other player that have lower level than you?:L

actually no, fire IS op, especially in a f2p vs f2p match up because of tobi....
In the long run thou, it depends on what rare ninja you just happens to pull more than the power of main char themselves (tobi being the only 100% guaranteed top tier ninja is the reason fire is so stronk)

If you got sage naruto and kazekage, your wind is looking up, but a mei will steer toward water or fire(ignition) for you. It all depends on the rare ninjas at late game.

Water isnt really good with f2p since needs lot of ninjas to work around ( Can work still )
Fire yes its easy to build as F2p player ( Overall easy class to build no matter p2p or f2p lol)
Wind Has same things to water and fire. Easy to build but to make it to other lvl need more ninjas to work around.
Lighting Yes easy to build as f2p same as fire. Lot of free ninjas works.
Earth. I would say not so easy to build. You get ninjas free what are useful to earth but most of them comes so much later lvls compared to other classes ( Well not for water since heck we don't get yet any those fancy ninjas to make us great)

But in overall all classes works both f2p and p2p but all classes needs time to get those ninjas around you to make it work. (Fire is easy road lol )

fire main with tobi is pretty broken till 2.0 comes out other then that go with the normal sasuke hinata water main and gnw kiba.


the other need set ninja to be good

Lightning, Hinata, GNW Kankuro and Sasuke.

I'd say all mains work for f2p you just need to be smart in anything, i'm a f2p i can compete with p2w's. I'm lvl73 fire main with 26k 2nd in most power. Just save your coupons for the events, do all events to make you strong and be smart :D

Honestly it depends on the ninjas you have but here is a thing for earth main: all the mains are good but they are all good in their own way.

An AMAZING team you c*e is this its OP: if you try the generator it might not give you a high combo. This is also for free players. THis team has a high combo and next level damage:

Earth main : SUPER stone fist jutsu, earth style - petrifiying jutsu, earth style - stone fist jutsu - fall, enhancment of earth style ninjas, steel body
TOBI:
YAMATO:
JUGO:

Summon : Flood Dragon (if you don't have it then you c*e the shark but the flood dragon does more damage, gives a higher combo, and is better MUCH better)

This team is OP

Earth main in the front, tobi behind him, yamato behing tobi and Jugo to the right of TOBI....

Fire is the best for me but it depends on your lineup imo.

I've been f2p ever since I started playing this game, which was a few months ago, and I have to say that Earth is one of the best mains to play as a free player.

water f2p
suigetsu, water main, gnw tenten, and any free tank- kimmimaro/kidomaru/hinata
id suggest kidomaru as it reduces all clones and lowers resistance turn 1
then turn 2 unleash watermains aoe
turn 3 kill the rest with gnw tenten

been using X X X
Light mc Guy Kimi
Sasuke X X
33312 with ninja cat ( if you'd have Fukurukumaru he'd be better)
and you can switch the last 2 talents to the sword user ones if you feel like it, this team helps a lot for gnw and Team instance since leeching counts for everybody on your side.
Only downside is that Sasuke tends to get killed of pretty easily so lookin for a replacement who might fill in his role Darui would be a good fit for 9tails with Kakashi then but haven't looked into this for a normal pve or pvp team

their is 2 ninjas that are bad moeji and udon

fire main is easy to build a team with

they are not hero they are ninja

Who best main for 2022?