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While almost all Minifigure torsos, arms and legs are the same size and shape, some sets and themes have included figures that differ from this standard minifigures.
Child-friendly versions of Minifigures, which are much more difficult to take apart, are being designed. Also, some of the newer figures have special features that can light up (such as lightsabers and flashlights). By pressing down on their heads, their flashlight part (which is also a lightsaber handle and is one piece with the hand and arm) lights up. While this adds a new feature, these Minifigures cannot come apart into as many pieces, which could discourage those who wish to customize them. The top of their heads can come off, because inside of that is a battery. However, it is not especially easy to do so and can damage them. Their heads can also come off, but it is not suggested because the heads connect to the body where the electricity travels to the arm.
Minifigures built from special pieces were first introduced in Star Wars. Martians are builds for five pieces: two double arms, mechanical torso, a combined leg piece and a head. This formula is repeated for many Star Wars droids. Battle droids follow the same pattern, while super battle droidshave the head fixed to the torso, General Grevious has space for four arms and IG-88 has a head constructed from LEGO elements. Other droids, such as Droidekas, Spider Droids and Pit Droids, are constructed entirely from ordinary LEGO elements many of which were originally made for the droid Minifigures, but are none the less often considered Minifigures. R2-D2, and other astromech droids, are constructed from specialized elements; with a separate top, body and two legs. Recently, the robots of Exo-Force have a design similar to the battle droids, but have separate legs and movable hands, and the head fixed on a small torso. The Minifigures C-3PO, Protocol Droid and TC-14 have a special molded head for characters in the Star Wars franchise. There are also Skeletons of a newer kind, who have a similar design to the battle droids. They still have a skeleton torso and legs, but their arms now can move articulately. In addition, in 2007 new Battle Droid arms were released, allowing droids and skeletons to hold their weapons straight up instead of sideways only. There have also been very rare Minifigures released, such as a 14K gold C-3PO which only 5 were made, a bronze Boba Fett and a silver TC-14.