From Worms Knowledge Base
This one is fired just like a shotgun, only with one shot and a big twist. The gamma shot that is fired can pass straight through terrain unhindered. When it comes into contact with a worm or object, that's when it takes effect. The shot creates no explosion (unless it hits a barrel or mine) but gives any worm it makes contact with a nasty cancer, which acts like a mild poison.
This shouldn't be at all difficult to progam in the slightest. The game will simply have to ignore land when the gun is fired. This weapon is useful for flushing out darksiders, but also makes a good darksider weapon as worms can use it from beneath the terrain. The ability to 'poison' a worm at long range is also useful. Although, because there is no risk to yourself, like there is with the skunk, some may see this as a weapon too easy to use.
This weapon really does remove a lot of the strategy from Worms, as it does not need to take the topology of the map into account. As a gun which always fires in a straight line, this weapon can therefore shoot anywhere on the map... and weapons that do that are not generally looked at with approval. It should be noted however that it can be very difficult to shoot someone from even just somewhat far away, even when the shot goes in a straight line.