My son recently started the game, and he is trying to level up some purple talisman. He has been grinding Garden of Dismay I trying to get purple one star evo runes. After 3 SOT refills he has received 55 blue one star evo runes and 0 purple one star evo runes. That’s not RNG - that is broken.

He is frustrated, is there another good place to find purple one star evo runes?