World of Padman is an open-source, cartoon-style first-person shooter game available for Linux too, besides Windows and Mac. It is a wonderful standalone game based upon the Quake 3 engine.
World of Padman (or WoP for short) features a cartoon-style approach, with maps, characters, weapons and sounds all based upon the Padman animation series. For example, the weapons include Punchy, a funny puppet used for close combat (which will also allow you to move faster), the Bubble G, which shoots bubble gums, or the Splasher, a sniper-equivalent from other games. World of Padman also includes four different player models, each with several other colour customisations.
One of the drawback is that currently (as of patch 1.2) single player mode hasn't been implemented yet, instead WoP servers are usually crowded and you can get playing online in seconds.
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