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This game has a curious history, having been created by Jenova Chen to accompany her master's thesis as a free Flash game in 2006.
The following year it was reworked into a PlayStation 3 game by her development studio, Thatgamecompany.
SuperVillain Studios developed a PlayStation Portable version of the game in 2008, and PlayStation 4 and PlayStation Vita versions in 2013.
In Flow, the player navigates a series of two-dimensional (2D) planes with an aquatic micro-organism that evolves by consuming other micro-organisms.
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The game's design is based on Chen's research on dynamic difficulty adjustment at the University of Southern California's Division of Interactive Media, and psychologist Mihaly Csikszentmihalyi's theoretical concept of mental immersion or flow.
In Flow, the player guides a small, multi-segmented creature in the form of a worm or snake through an aquatic environment full of beauty, serenity and mystery as it journeys through various levels and wondrous environments.
As the creature progresses through the levels, it will encounter other life forms, environmental challenges and opportunities to grow, adapt and transform into a more powerful and versatile creature in its quest to dominate its aquatic environment.
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With its stunning visual design, immersive soundtrack and intuitive gameplay, ‘Flow’ immerses players in a world of exploration, discovery and connection with nature that invites them to relax, reflect and enjoy a unique and rewarding experience.
The PlayStation 3 version of Flow includes visual enhancements and three additional playable organisms: one that can move with a short burst of speed, one that can paralyse other creatures and one that attacks its prey's weak spot.