I’m mostly talking about a good composition, because I have trouble deciding which heroes I should combine together. For example, I have absolutely no idea where would I ever put Ursula.
List of most of my heroes:
My constant 5 is definitely Maleficent, Mike, Calhoun, Violet and Ralph, but I just can’t make the other ones to work.
I’m aware that sometimes you switch heroes around, but I’m looking for a base from which I could go forward.
I’m on server 6, so lvl 95 and O1 is max currently.
Um. If you have Elsa consider making a Freeze team of: Elsa, Olaf, Walle, Frozone, and possible Felix with Frozone’s disk.
You will find that Flynn and Tia Dalma will prolly be useful as one curses and the other removes debuffs. You will also want Quorra as high as possible. And I personally think Judy with Felix’s disk is amazing. Sulley can be a team healer since he has the Woody disk just watch out for Tia’s curse! Maybe putting him with Flynn? Someone else may wanna correct this just thought I could give you some ideas…I hope this helps and isnt completely useless information you already knew 
I’d say team 1 ralph, sulley, mike, buzz, Calhoun with her violet disk is good
Ralph is good because he stuns and heals because his jack sparrow disk.
Sulley is good because he heals everyone 20% per disk star of healing laughter with woody disk. Which is like 5k? 6k? Which is a Lot!
Mike is good because with sulley’s scare and disk he’s a stun and energy machine.
Buzz is good because of his zurg disk he gets a lot of atk speed from his power up skill.
The biggest thing with Colosseum is making sure you have 3 unique teams each with a designated purpose or overall idea. There are 3 basic categories to go for that. First is Fantastic Damage, Second is Normal damage and last is some sort of defensive oriented comp. Such as a shield stall or a control heavy composition.
For Fantastic damage the typical form is some sort of Scare comp utilizing Sulley and Mike 9/10 times. You can use Hades and Jack Skellington if you have them strong enough but most of the time it will be Sulley, Mike and Zurg. Standard set up there would be as such: Sulley(Wo), Woody(Bu), Zurg(Re), Mike(Su), and Flynn(Qu).
Next for basic damage comps or normal you want characters that can study enemies to allow your auto attacks to always crit. Most of the time this will be Baymax but Barbossa cpuld once again work if you have him strong enough. A standard set for that would look like this: Baymax(Wa), Moana(Me), Judy(Fe), Mickey(Su), and Calhoun(Vi).
Lastly there are your stall and control comps either of which are solid for you. Both work to either stall out the last round of defense or prevent the enemy from doing much of anything. For control basic set up would be along these lines: Ralph(Ja), Wall-E(Da), Tia(Ya), Ursula(Ti), EVE(Ca). Then for shield comps you can look at something like: Bogo(Mr), Violet(Me), Quorra(Buzz), EVE(Wa), Calhoun(Vi).
Hope that gives you some direction. Obviously there are more comps that can work those are just basic archetypes to follow.
