Spider (Big Ass Spider)

The Spider is the main antagonist of the 2013 comedy-horror film Big Ass Spider. Once a regular spider, it became a feral monster infused with alien DNA that seeks to destroy LA and make its new territory.

Biography
When scientists were testing out a sample of alien DNA, they tested it on fruits to make a growth hormone. A spider was residing in one of the test fruit and was also infected by the DNA, causing it to not only rapidly grow over time, but twists its personality into an extremely ferocious creature. The scientists discover the spider and inform the military, but the spider hides in a body bag.

The body bag is moved to a Los Angeles hospital, where the spider crawls out before biting a mortician and escapes into the air vent, where it enters another room and kills an elderly patient. It hides in the basement where Alex discovers it. Just as Alex was about the kill it, the militia appear and open fire, scaring the spider away. It escapes down a grate into the sewer where it kills a hobo.

Alex and Jose track the spider to a park where it kills dozens of people. They draw it to their truck and attempt to lure it towards the military forces, but it retreats into the forest once they open fire. The squad pursues the spider, only for it to ambush the troop, killing a majority of them and capturing Karly. Afterward, Braxton reveals to Alex and Jose about the alien serum and the test fruit, believing that the spider will soon reproduce once it reaches its max size.

The trio head toward downtown, where the now enormous-sized spider sets its nest in the US Bank Tower. At the top, they discover that the spider laid eggs in the building, using Karly and many other kidnapped citizens as food sources for its offspring. They manage to rescue most of the victims as the babies start to hatch. An airstrike commences that destroys the nest and kills the spiderlings, but only aggregates the giant spider. Remembering how flammable the spider's webbings are, Alex instructs Jose to grab a rocket launcher from a military vehicle, toss it to him, and fires a rocket straight into the spider's spinneret, causing it to explode internally.

Trivia

 * The jogger that the spider kills in the park was Lloyd Kaufman, the founder of Troma studios and director of The Toxic Avenger, which he wore a T-shirt of.