This card reminds me of Gnome Gemfinder.
I thought of the mechanic I want to use for stones/gems Sacrifice ? number of Stones/Gems to gain a Pillar/Tower of its element.
Whenever I think of a Gem Series I think of Ajit.Tough to think of a Gem Series by anyone else to be honest, and more so if the mechanics are being figured out by the community.
How about they Generate their element and Sacrifice Stone reduce Activation costs/ Gems change and/or reduce Activation costs.