Click the link - it’s a bad ass video!
Cone snails are the largest known genus of invertebrates. They eat molluscs, worms or fish, which they catch using “harpoon-like” spears that are loaded with a venom containing up to 200 different toxins, and Conus geographus (featured in the BBC video) is the most venomous of all.
Cone snails are efficient little factories of death. They manufacture and store little hollow harpoons in a sac in their body, and they have another sac which synthesises venom.
The harpoons are loaded into the proboscis and then armed with venom when they sense their prey.
Fish-eating cone snails like the Conus geographus only use a harpoon once. They swallow it while digesting their prey.
The venom is neurotoxic, essentially working to paralyse their victims. The toxins have been researched and developed into a painkiller for cancer patients and is said to have similar properties to morphine.