Armos Titans are enemies from early, unreleased versions of The Legend of Zelda: Twilight Princess. They are a more muscular, humanoid version of the typical Armos. Unlike the regular Armos, however, their weak spot is a jewel located on their chest instead of the back.
Upon defeat, Armos Titans stand in place, unlike the normal Armos that explode when destroyed, although they have death animations that make it look like they were meant to explode when defeated. However, these animations were never programmed into the Titans' AI.
Interestingly, Armos Titans somewhat resemble the Sacred Grove Guardians; it is possible that the Guardians' design was inspired by that of the Titans.
Additionally, they have two different animations for waking from a "statue" state upon sighting Link; one for getting up from a pose where they are on one knee and have their palm raised in front of them, and one that is simply a mirrored version of this. This could point to them possibly being fought in pairs, positioned next to each other or on opposite sides of a doorway.