I’m not sure if there’s any existing thread regarding to this matter, but I hope EnP would consider to add one more battle item slot when fighting advanced level or stage that required maybe around 3000 to 3400 team power and above? Or maybe for fighting titan with 6* and above?
So for normal to medium quest level, players can use 4 slots only. (currently)
And for fighting hard and above quest level, players can use 5 slots to place battle items.