Missing a max sig crystal?

Dragonplumber_1

I don't know if I am supposed to get a max sig crystal everytime but I just maxed out my 2nd 4* champ and got nothing but the usual stuff you get from getting a duplicate champ.

Mitriax

You don't get any extra when you max out.
It's when you duplicate after that.

Dragonplumber_1

Alright thanks.