This guide showcases situation specific team compositions that might help you progress. As a rule of thumb you should use the heroes with the highest ascension tier available to you in a composition that maximizes the faction bonus, but sometimes a single substitution or quirky line-up change can make all the difference. Most of these teams have been assembled and tested by me, others were submitted by a good friend of mine or observed being used successfully in the arena/ legends' challenger tournament.
1. I´m walking here

A team comp that's effective against enemy teams that heavily rely on their warrior and agility type heroes (Ankhira, Golus, Grezhul, Brutus, Baden). Rosaline will soak up a little bit of damage while dragging the enemy frontline hero to Lucius where a cluster of enemies forms that'll be taken out by Belinda's enormous aoe damage. Athalia and Fawkes provide the much needed CC and distract or even kill the vulnerable enemy backline.
Pros: Satisfy your thirst for Belinda's lightning showers.
Cons: Athalia is difficult to ascend, and if your Rosaline is severely undergeared she might not be able to survive her stroll. Struggles against tanks which can displace Lucius, Arden for example.
2. Shemira and the Battery Packs

What this team lacks in single target dps it makes up for with Rosaline-/Rowan's energy restoration capabilities. As those bars are filling up Rowan's potent potions and Nara's ability to lockdown the enemy carry are what's keeping the team afloat. If Shemira survives long enough she will quickly turn the tides of the battle with consecutive ultimates.
3. The Midgame Powerhouse

Powerful midgame composition with just enough CC to keep your frontline alive.
Disadvantages: Saveas needs to be overleveled for this to work.
4. Tornadoes and Wrecking Balls

The fight for Middle-earth and make Master Splinter proud line-up doesn't disappoint when it comes to aesthetics. Fortunately, it packs a punch as well. This 4+1 formation provides the much appreciated defensive faction buff for Eironn. Position him in the middle for maximum efficiency.
Pros: Looks cool and annihilates certain teams within seconds. Solid for pvp.
Cons: Eironn and Gorvo can be overwhelmed by the enemies Eironn pulls through his vortex ability. Not suitable for pve until Eironn and Gorvo have reached mythic tier and seen their respective signature items unlocked.
5. Wrizz' Nightmare

Another midgame Lightbearer team. Lucius shields the team while Raine and Estrilda boost the numbers. Shemira can replace Belinda. For the endgame I'd suggest something along the lines of Warek or Raine, Shemira, Rosaline, the twins(Elijah & Lailah) and Baden.