Suggestion: Spirit Gem to merge several skills into one.

Spirit Gem: Combine Skills (Limit: 1 such gem per character, reserves 30 Spirit per skill slotted, minimum level 8 Spirit Gem to create)

Mechanic: All skill gems slotted in the Gem activate simultaneously with the same target, using all resources those abilities normally use. If you don't have enough resources to use all the slotted Gems, this fails. Any modifiers slotted in this will alter all of the slotted skills, and the slotted skills use their own level, not the level of the gem.