Boltcaster

The Boltcaster is a weapon in Deus Ex: Invisible War. Like the Mini-Crossbow, it fires a poison-tipped dart, which will slowly damage the enemy until he falls down unconscious. The only groups that seems to use Boltcasters are Order Seekers and the occasional Thug. It's alt-fire is a scope, which makes it extremely useful for long range.

Strategies
The Boltcaster will be your primary ranged weapon in a pacifist run, as it does not kill enemies. However, make sure to fit a Silencer on the gun; the Boltcaster's firing sound can be heard by enemies if it doesn't have one.

In a non-pacifist run, the Boltcaster can be useful to help soften up a strong enemy, (such as an Illuminati Commando). After firing a few shots at the enemy, switch to your primary weapon and finish the target off.

Variants
There is only one variant of the Boltcaster; the Hellfire Boltcaster, which is located in Dr. Nassif's greenhouse. Unlike the regular Boltcaster, the Hellfire sets enemies on fire. Obviously, this only makes it useful for a non-pacifist run, but this makes it much better for softening up strong enemies.