Multipede

The multipedes were a new species of giant cave dwelling centipedes that were inadvertently created by the Cabal.

When the Cabal was on a decline and nearing their end as an organization, they wanted to cover up their tracks and leave a path of scorched Earth behind them. In doing so, they made sure to destroy all of their research materials before destroying the entire site location as well. There was a secret bunker lab in an underground cave in the Colombian highlands where the Cabal had kept and researched the source blood. After the Cabal self-destructed the lab, the remaining source blood seeped into the ground, attaching itself to the mineral content in the walls of the cave system causing the local centipede population to mutate into the multipedes.

Nikola Tesla came to the site in search of the source blood, but instead only discovered the multipedes. The multipedes didn't kill him, but instead wrapped him in some kind of biological material that Magnus described as a protein column surrounding a hollow tube, like hair or veins. Nikola deduced that the multipedes probably kept him alive for as long as they did because he shared the same blood type as them.

After Magnus and the Sanctuary team rescued Tesla, Magnus destroyed all the multipedes by detonating a bomb in their nesting site which was located inside the Cabal's secret lab. Magnus didn't like the non-naturally evolved "abominations" created by the Cabal's recklessness due to their propensity to potentially burrow their way across the entire continent; possibly decimating entire ecosystems along their way. She also had a deeply personal reason to destroy them so that nobody could try to recreate the source blood and or the effects of the source blood EVER again.

When leaving the caverns, Tesla had tried to smuggle a multipede larva with him so that he could use its blood to try to create a serum that'd duplicate the effects of the original source blood in order to re-vamp himself. Magnus, however, took the larva from him at some point after they reached the surface.