Tablet of Truth

You defeat a pair of Guardian Kin and make your way into a protected vault. Inside is a tablet with familiar inscriptions. Your intuition tells you that this language can be deciphered rather easily... However, once you begin deciphering you'll be locked in. The tablet gives off a soothing energy and you can smash it to receive its healing energies instead. Decipher Lose 3 Max HP. Upgrade a random card. Or Smash Heal 20 HP.

Source: Untapped.gg. Full branch text may continue on the official detail page.