You need energy to explore rooms and play mini-games. The amount of your energy is limited, but it restores over time. Also, when you gain a new level, energy is fully restored, and its maximum capacity increases.
Don't want to wait? Use food from the game store to partially or completely restore spent energy.
You can get food or energy itself as a reward for charging collections, completing quest chains in a room, as well as during holiday offers, competitions, and seasons. By restoring energy with food, you can get more energy than your cap allows. The surplus will not be lost.
Energy regenerates at a rate of 1 unit every 3 minutes. You can accelerate it by 3 times with the help of special amulets: they differ only in duration.
The rewards for competitions, seasons and holiday offers can sometimes grant you the so-called "endless energy". This effect allows you not to waste energy at all, but its duration is limited.