Experience Scroll (level 20)
Experience Scroll is a consumable that increases the character's level to 20 if that character is below level 20. It is a reward from Massive Achievement Chests received as part of the achievement rewards, and is also a birthday gift.“
Double-click to consume.
Double-click to advance a character to level 20.
Can only be used by characters under level 20.
— In-game description
There are three variants of this scroll. One variant is from achievement chests, another from first birthday and the last from second birthday. While they stack with themselves, they cannot stack with each other.