A Giant Snakehead would take on a Piranha of the same size anytime, small fish are taken in a gulp, bigger fish would have half of its body gone before taking the other half or leaving it as its mark. A Giant Snakehead can handle itself alone, but a Piranha is only deadly when it's in packs. It takes a pack hunter of Piranhas to murder a man, but it only takes a single huge adult Giant Snakehead to do the job.
For a predator that breaks tank glass, attacks its owner, cleans tankmates, cuts wires, breaks lures and even up to killing swimmers, a Giant Snakehead is clearly a living torpedo in the water. Below are pictures of attacked Piranhas, a young juvenile ruling a Piranha tank as said by the owner himself as well as pictures of their teeth~!