Quell is a Relaxing, Hand-drawn Puzzle, and Single-player video game developed by Fallen Tree Games Ltd and published by Green Man Gaming Publishing. The game lets the player experience enchanting puzzle gameplay full of relaxing and logic. However, the gameplay is quite simple, in which the player needs to slide the bubble of water around a window-pane while avoiding the obstacles including spikes and others. During the gameplay, the player needs to gather the pearls and test his logic in each level. There are lots of challenging levels, and each level comes with a unique way to complete it. In the game, the raindrop will move until it hits a wall and the raindrop must touch golden balls without getting trapped or hitting spikes. Further puzzle elements are also present, including blocks, switches, gates, and more. Quell Reflect, Quell Memento, and Quell Zen are later sequels of this game. The game takes place in the 2D world where the player navigates the stage from a top-down perspective.