Once you have Summoned a Costume from the Costume Chamber, it can be levelled-up to make it more powerful. You level your Costume as you do your Heroes, but you may also use duplicate Costumes which will give you more experience. 

Levelling a Costume gives you increased experience points and has a reduced food cost per level (compared to levelling a non-Costumed Hero). 

You may also Ascend your Hero Costume, however, the material and resources to Ascend a Costume are also much less than what is required for a non-Costumed Hero. 

Please note that a Costume’s Ascension tier cannot exceed the Ascension tier of the base Hero. To fully level a Costume the Hero must also be at the final Ascension tier. 

For more information or Player Guides on using Hero Costumes, or any other gameplay questions you may have, please visit our Community Forum