Mister Cheif
From Halopedia, the Halo wiki
Bungie
Mister Cheif is Master Cheif but basciclly the joke of Bungie. Frank O' Conner created Mister Cheif and every week at the end of weekly updates he adds Mister Cheifs at the end.(fan asked drawing of him.)
Halo 2
Now Halo 2 had updates just as well. It also showen Mister Cheif.