The water level is a trope of platforming and action games, and some FPS games. This type of level is characterized by an environment covered in or completely submerged in water. The water is typically used to affect the player character's movement, making them move slower, often with "floaty" movement and an effective increase to their jump height. While in the water, the player's height may drop over time or they may be able to float static in any section of water. In this state, they are also effectively able to move an unbounded distance in any direction, whereas most platformers usually limit the player's movement along the Y-axis with a strong gravitional pull. Movement through a water level may also be affected by running streams, strong currents or waterfalls. These geographical features may push a player in a certain direction, meaning that the player must course correct when moving through them or avoid them entirely.
Depending on the game, the water may pose be a drowning hazard to the player character. Over time, the character runs out of air and dies should they be starved of oxygen entirely. A warning sound effect or music typically accompanies this proximity to death. In these scenarios, it is common that players can refill their air supply by finding oxygen sources or rising above the water. Ecco the Dolphin and Sonic the Hedgehog feature particularly famous examples of these drowning and air refill mechanics. Water levels have historically received a mixed reception among gamers, garnering criticism for their restriction of player movement. Many 3D subaquatic areas have also been criticised for being difficult to navigate due to the player being provided full range of movement along all three axes.
Water levels may contain appropriately-themed enemies such as fish, sharks, squid, urchins, crabs, and other underwater creatures. In relatively modern games, they also have been a vehicle for developers to showcase realistic water graphics, one of the more technically challenging areas for software engineers due to the complex reflections, refractions, and fluidity of water. Water levels have often also been accompanied by distinctive water-themed music which often makes use of strong reverb, notes held for long periods, and/or "chilled" sounds. The underwater theme from the original Super Mario Bros. and the Dire Dire Docks theme from Super Mario 64 constitute some of the most famous water level music in games.