Hives have 1 offensive and defensive weapon; carapace armored egg pods. They do everything. Shotgun minigun style.

Edit; well, they do have their smog-gas which is radiated gunk mixed with oxygen and hydrogen and other things, it's the give off from how the Hive's create oxygen for themselves and the Esurienti that infest them when in space. But I doubt radiated smog would do much even if they expelled all of it.