Blue Power Crystals and Red Power Crystals are powerful items that will allow you to reduce the level up and promotion cost of your Super Managers!
On the "level up" or "promote" panel of the specific Super Manager that you would like to upgrade, you will be able to tap on the relative Power Crystal icon and use as many as you wish.
Each Power Crystal used will reduce the required cost of Blue or Red Gems by 50%. You can use multiple Power Crystals at the same time to further decrease the upgrade cost, with 0 being the cost limit.
Power Crystals will be made available in the upcoming weeks from in-game Events, so stay tuned!