IF you play this game (for obv reasons), do us all a favor and do not financially support the dev/publisher. I have seen this sht at least thrice (incl. a h-ver) and never the dev attempted to improve it in any way. Still abysmal power curve, disproportionate resource with no respect system, idiotic hero designs (like healer that will only heal highest atk unit, even it's full hp, or tank with a dps kit!), three separate currencies to used for summon (gem is universal but it's rewarded extremely pitiful thru playing) and a general lack of storyline plus many QoL features make up an 'idle' game.
7sins X-tasy is out, it has plot + "plots" (find 18+ apk on their web), and shit tons of freebies. Go play that sht.