Liquid Kids is a single player platform game that features Hipopo, a platypus (referred to as a hippo) who must fight his way through a large number of enemy-packed levels in search of his missing girlfriend - rescuing other platypuses along the way. Hipopo is armed with water bombs which can be thrown at enemies to soak and damage them. Once soaked, the enemies can then be kicked and destroyed completely. Enemies left unkicked however will dry out and recover after a short period of time.
The level design presents moving platforms, collapsible floors, boats and water-wheels all making an appearance. Small plants also appear on certain levels which can be "watered", causing them to grow and creating new platforms. Appropriately enough for a game which features water as the main weapon, many of the enemies and the later levels have a fire thematic. He can also collect cakes and other items to gain more points.