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Iikka Keranen
When one thinks of people that helped to shape the current way levels are created, a name that will always crop up into the list is Iikka Kernanen. Iikka was one of a few pioneer level designers that created the new bottom line for playability and design in Doom levels, as well as helping to develop some of the special FX that many level authors now take for granted. His background is extensive, with level sets such as Addictive DM, Dystopia 3, Requiem, and GothicDM (among many others) on his list you can instantly tell the man has talent. Since his time developing levels for Doom, Iikka has moved into the realm of creating levels for Quake. Possibly his best known work being AirQuake. And currently, Iikka is employed with Ion Storm, working on the Anachronox project. Iikka, truly did help set a standard for Doom level design, that even over the past couple of years since he stopped making levels is still considered of the highest quality. 
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