Many of the players use single color stacking for titans, raids, challenges, etc…
Lets see who you must have to in each color (minimum of 3 heroes as the other 2 could be replaced with different options) and it doesnt matter if its 4 or 5 stars as aome 4 stars buffs are mandatory
I will start:
Yellow (holy): Must have G. Jackal, Wu, delilah (for her base attack minions and healing)
Optional: Joon, Poseidon
Or any other sniper or hitting all target to have better chance when wu is activated
Purple (dark): must have G. Panther, kunchen or Tib (for extra defense down), Kage or Sabina (to remove the buffs)
Optional: any snipers, Mok-Arr for his high attack and will not affect your team, victor for very fast and high base attack
Red (fire): Must have, Falcon, Wilbur, GM
High recomendation: BT
Optional: marjana, azlar, colen, Santa
Blur (ice): must have Frida, kiril for his healing and attack/defense buff, Alasie
Optional: isarnia, magni, grimm many will work as optional heroes
Blue was very hard to have a must heroes any other options??
Green (nature): Must have Evelyn, Zeline, Lianna
Optional: Melandor, Buddy, MN, any fast 5* hero
The list above are the heroes i would like to have foe stacking single color
Lets have your thoughts about each color and what are you options