Gems are the premium currency of Castle Clash. They can be used to buy Gold, Mana, Honor Badges, Heroes and additional Builders. Gems can also be used to rush building time, to revive heroes and to roll for new Talents. Gems may also be earned through Achievements and daily gifts. Gems can’t be used to buy Hero Shards.
The best use of gems is probably buying random heroes or trading them for Honor Badges in the shop. A hero bought with gems will be more likely to be legendary than one bought with honor badges. Rolling random Heroes with gems is the only way to get a Pumpkin Duke, Snowzilla, and Cupid.
Gems can be purchased either by clicking the “+” next to your Gem amount in the top right corner of the screen, or by opening the Shop and clicking on “Treasure”.
The current rates, without any sales, is as follows: