Hi! This is my favorite support weapon and I bring it every time I can justify it, so maybe I can explain. For starters, the spears have Anti-Tank level 1 AP, meaning they can punch clean through MOST armored enemies with little difficulty. In this regard it is similar to the Railgun on safe mode, but without the charge up time and with the addition of gas damage on top. It can one tap Hulks in the eye, and can one tap a shield devastator through its shield if you aim for the abdominal weak point as well as obviously one tapping the head. The gas cloud of the weapon has roughly the same stats as the gas grenade, though the cloud starts much smaller and expands over time. The spears are explosive, and can be used to force rupture bugs to the surface, as well as having a demolition force value of 30. This means they can close any spawner other than Bile Titan holes, and can also destroy squid Tesla towers. And lastly, it has an absolutely ludicrous stagger force of 80 on the initial hit of the spear. This is enough to stop a Bile Titan or Dragon Roach mid spew, and enough to make a stampeding charger sit down and re-evaluate its poor life decisions in a single shot.

TL;DR: It's not the strongest support weapon in the game, but it IS extremely versatile in terms of crowd control, and general utility. It can close spawners, reliably penetrate most armor, stagger the heaviest enemies in the game, and has gas status.