From Halopedia, the Halo wiki
Square Enix is a Japanese video game and publishing company, best known for its creation of the Final Fantasy, Dragon Quest, and Kingdom Hearts series. A subsection of the company, called Play Arts Kai, is notable for making action figures of characters from Final Fantasy and Metal Gear Solid.
Their figures are highly articulated and detailed. Square Enix had actually received 3D data from Microsoft. Using the computer models, they cut out the figures until the appearance was "towards its exactness". Sculptors then added details to the figures and decide how to add in the articulation before painting.