In addition to its 100% critical chance and high damage, the Firelance sets its target on fire upon strike, causing 2 points of damage every second for 5 seconds. Both the Pyromaniac and Xenotech Expertperks affect this weapon and it uses the rare alien power cells as ammunition.
This weapon is perhaps the rarest weapon in the game as it has no guaranteed location where it will always be found. When paired with the complication that a player needs to be alert to the event that spawns it, and that the weapon and its ammunition scatter randomly across the location of the event, the recovering of the weapon can be difficult or even impossible even to an observant player. However, If Dogmeat is currently following you, you can command him to find the Firelance and the ammo, making the search easier.
The Firelance event produces a brief radiation field which is usually centered on the weapon itself. The weapon may not always be found within the irradiated area but will usually be very nearby.
The Firelance can get stuck on buildings, like a water tower in the Wasteland.
If the Firelance event took place and you are having trouble finding the weapon, if you have Dogmeat as a companion you can have Dogmeat search the area for the Firelance and the ammunition. If you do not have Dogmeat as a companion, a less desirable option is to keep the sound effects volume turned up and listen for the sound of your foot "kicking" the weapon when you walk around the area the explosion took place.
If the Firelance event took place near hostile non-player characters, they may utilize the Firelance. This can be used to your advantage. If the Firelance has fallen on top of a building the non-player character will take the Firelance to use, even if you couldn't normally pick it up. Simply kill them and take it off their corpse.
Normally, this weapon is weaker (but still very hard-hitting) than the alien blaster due to its burning effect. However, with the Pyromaniac perk, its power exceeds that of the blaster. It still wears down significantly faster, though.
The Firelance is a reference to an identically named martian weapon appearing in the Wasteland paragraph book, in the red herring Mars plot.
Both the Firelance and the alien blaster resemble Commander Adams' pistol from the 1956 movie the Forbidden Planet, both in design and firing. The "bullets" disperse in a very similar way when they hit solid objects, such as walls.