Spirit Tonic or ST, is an item which can be used to restore 100 Spirit Power during the Underworld event.
Unlike the bound version, these variant can be traded or gifted to other players. Usually players have to pay several Power Potions or Energy Drinks for one Spirit Tonic.
Spirit Tonic can be bought in the Shop from the start of the Entry Period until the end of the Underworld event. One Spirit Tonic costs 100 Gems, but usually there are special price offers available.
Spirit Tonic is also often added as a bonus to Card Packs.
After the end of the Underworld event one Spirit Tonic will be converted to one Power Potion.