SD - Super Deformed

Although the stories themselves are parody, SD Gundam models is a serious business. While regular Gundam model lines strive for realism by introducing High Grade, Master Grade and Perfect Grade models, SD Gundam models are designed for (and sometimes by) the customization crowd. Many SD Gundam models are designed such that variations of the stock models, as seen by SD Gundam comics, can be made by using parts from other SD Gundam kits. Modifying SD models is very popular in Japan, more so than the full-sized counterparts. In addition to made-up robots contributed to SD Gundam comics, Bandai also held monthly contests for custom Gundam (usually Musha-based) models.

Some SD Gundam models can be combined into a non-SD unit, either by design or via customization. Alongside SD kits of standard Gundam mecha, each year usually offers a stand alone line (usually supported by a separate manga) with each of the kits sharing a common gimmick. As of early 2006, the current line are designed as combiners. Whilst each kit can build a Gundam with at least two forms, all of the kits are designed to double as part of a combined form in various ways.