My son Jareds favorite game and character, has been for a few years now, problem was and still is, since Halo is rated MA for mature adults no one makes a child size costume for him, the helmet/mask is available for kids, but no costume or accessories. So enters super dad, lol, I bought a double extra large, i.e. XXlarge and had to size down to a small 12 year old boy size, not an easy task, but with some imagination and creativity and some patience from a 12 year old (no easy task i tell ya) as I am sure you can relate, i was able to scale down this enormous costume to fit my buddy boy and make it comfortable enough to trick or treat in. He said that everyone who seem it loved it and it helped to keep him dry this rainy Halloween.