This is a video of several xenophyophores, four-inch-long single-celled organisms that have been discovered 6.6 miles under the sea in the Mariana Trench.
Last July, engineers from National Geographic and UC San Diego's Scripps Institution of Oceanography found this particular batch of xenophyphores when they sent untethered dropcams into a region of the Mariana known as the Sirena Deep. They're no gelatinous cubes, but they're impressive globs nonetheless.
Little is known about these massive amoebas, but they live in one of our planet's least accommodating ecosystems. The cold and pressure of the Mariana Trench are certainly inhospitable, and the deep-sea environment leaves the xenophyophores awash in and resistant to toxic metals like lead, uranium and mercury.
The xenophyphores don't travel far out of their otherworldly deep, but at least they have company — the dropcam team also spied the most-deep-sea jellyfish yet discovered.