Poison in a can

This is more like a futuristic weapon. This is known as the VX Smoke grenade. In Special Force, this grenade creates a toxic cloud which destroys the nerve systems of anyone who passes through it.

Now if this was a real weapon, this weapon would be more likely used by terrorists for biological warfare. The details of this grenade is that it is x10 more poisonous than Sarin and really paralyzes people who walk into the smoke. It is a good thing that people have already invented gas masks to save us from biological war fare.