Will I lose the costume of a 5* if I retrain it in the Hero Academy ?
If you only have ONE of the costumed hero and you use that to train in Hero Academy Lvl 10… you’ll lose that hero, and the corresponding costume version of the hero.
However, if you get another of that hero in the future, the costume version will still be available, because the costume itself stays in your inventory. Just go to Menu > Inventory > Costumes to see those. They remain there even if you feed away the actual hero.
Keep in mind though, that if you have already partially leveled the original or costume version, and then feed it away… if you get another in the future, the new hero and its costume version will both be at Level 1-1. For example, if you have Vivica at 3-70 and Vivica Costume at 3-70, and you decide to use that Vivica to train for Lvl 10 in Hero Academy… you’ll essentially have wasted all that leveling that you did to get them both to 3-70.
Use a 1-1 Quintus or other such garbage hero instead.
Thank you so much for your speedy reply !