The thermic lance is an industrial metalworking tool with a built-in power source that heats the tip of the device to a very high temperature; the tip is then driven against the target, severely heating anything it touches. It is heavy, but deals considerable damage because its continuous penetrating action allows it to bypass the target's Damage Resistance and Damage Threshold. It is very durable, and also resists damage to itself if hit when used defensively (taking only 0.5% of normal durability damage). However, due to its automatic attack-type, it will degrade at a faster rate than other weapons when used.
Unlike most melee weapons, holding down the attack button when wielding the thermic lance will cause continuous damage to targets in contact with the tip. While it has a relatively low critical damage rating and critical chance multiplier, both are offset by its automatic operation, which gives approximately 5 chances per second to inflict a critical hit.
The thermic lance's V.A.T.S. attack animation is unusual, due to the automatic nature of the weapon type. The attack is initiated but the automatic damage is not applied, nor does the target act as if harmed, until the end of the attack when the damage is finally applied. It also has a slight knockback effect.