Games such as clash of clans and clash royale or other games that have an alliance feature also have a requesting/sharing feature amongst alliance members. I believe that this feature could be beneficial to the game. Possible items to request/donate:
In return for donating, the donator could receive XP or there could be a donation chest with each donation giving you a point until you have collected enough points to obtain said chest. This chest could be a max level XP card to level up heroes or possibly gems. There would obv be a cooldown and a cap to the amount one can donate/request, but with an active alliance, all members can potentially benefit.
I also feel like this idea could be expanded upon, hence my posting it to this forum as apposed to directly contacting the developers.
What other items could be requested/received and what other ways could donations be rewarded?