Rules to upgrade and reverse Hero's stars

Hero's star upgrade:

4-star SR can be upgraded to 5-star SR, 5-star SSR can be upgraded to 9-star SSR, 5-star SSR+ can be upgraded to 11-star SSR+

Conditions for upgrading to 6 stars: 1 5-star identical hero + 3 5-star heroes of the same clan.

Conditions for upgrading to 7-stars: 4 5-star heroes of the same clan.

Conditions for upgrading to 8 stars: 3 5-star heroes of the same clan + 1 6-star hero of the same clan.

Conditions for upgrading to 9 stars: 1 5-star identical hero + 2 5-star heroes of the same clan + 1 6-star hero of the same clan.

Conditions for upgrading to 10 stars: 2 5-star identical heroes + 1 6-star hero of the same clan + 1 9-star hero.

Conditions for upgrading to 11 stars: 1 6-star identical hero + 1 9-star hero of the same clan.

Hero Reverse: Heroes above 5 stars can be returned to 5 stars, and gives back the corresponding development materials

6-star return: Return 1 same type 5-star hero and 4 5-star heroes stone of the same clan. Heroes stone can be used as any 5-star hero of the same clan.

7-star return: Return 1 same type 5-star hero and 8 5-star heroes stone of the same clan. Heroes stone can be used as any 5-star hero of the same clan.

8-star return: Return 1 same type 5-star hero, 11 5-star heroes stone of the same clan, and 1 6-star hero stone of the same clan. Heroes stone can be used as any 5-star hero of the same clan.

9-star return: Return 1 same type 5-star hero, 14 5-star heroes stone of the same clan, and 2 6-star heroes stone of the same clan. Heroes stone can be used as any 5-star hero of the same clan.

10-star return: Return 1 same type 5-star hero + 16 5-star heroes stone of the same clan + 3 6-star heroes stone of the same clan + 1 9-star hero stone, the same as above.

11-star return: Return 1 same type 5-star hero + 16 5-star heroes stone of the same clan + 4 6-star heroes of the same clan + 2 9-star heroes stone, the same as above.