Alien (Mammoth 2006)

The Mammoth is the main antagonist of the 2006 film under the same name. While the Mammoth corpse itself isn't extraterrestrial, its existence is indeed the result of alien interference.

Description
The exact alien lifeform appears to be a slime-like organism, it is shown to be capable of controlling and resurrecting deceased bodies in order to adapt to foreign landscapes. In this case, its took control of a Columbian Mammoth corpse to adapt to Earth's foreign conditions. The body itself though is missing flesh and skin due to it being frozen for so long.

While having many of the main abilities of the creature it's host of, the alien lifeform can seemingly drain lifeforce out of other organisms. For the Mammoth, it does this through its trunk.It is also apparent resistant to burning metal, which under normal circumstances would've burned away the flesh completely.