a) You will be able to obtain 1 Gem upon getting a new hero for the first time. The quickest way to obtain new hero is via “Friendship Gacha” or “Premium Gacha”.
b) By maxing up the hero level also provide you with xx gems. This gems rewards is determined based on the hero.
c) Fully awakening the hero through the barrack will also provide you with xx gems. This gems rewards is also determined based on the hero.
Join a guild or add plenty of friends and select their hero as helper on the battlefield.
You will obtain +5/+10 Friendship per attempt. Once you have collected 200 friendship points, you will be able to gacha once in the”Friendship Gacha”.