https://www.dengekionline.com/news/20...2_10_mgs31.jpg
This is pamphlet given out during E3.
https://www.dengekionline.com/news/20...2_10_mgs32.jpg
Inside the pamphlet, there is shape for paper figure. Hideo Kojima had said that it is a figure for Metal Gear Rex, but he also mentioned that there will be parts left over to reveal a secret weapon for Metal Gear Solid 3.
https://www.dengekionline.com/news/20...22_10_mgs3.jpg
Dengeki Online has assembled the left-over part and made it into the figure above: caterpillars in the bottom and a missile (nuke?) on top.