Foes killed by your Energy Weapons emit a corona of harmful energy.”— In-game description, Fallout: New Vegas
When a target has its hit points reduced to 0 by an energy weapon, this perk will trigger an explosion centered on the target, similar to a plasma grenade explosion, but smaller. The explosion can cause critical hits and sneak attack criticals, potentially killing nearby targets, propagating further meltdowns and creating a chain reaction. The player character and companion characters are not immune to damage from the Meltdown effect.
The damage dealt by Meltdown is relative to the damage dealt by the weapon that killed the target. A powerful weapon, such as the Gauss rifle, can trigger a meltdown dealing upwards of 300 damage whereas a flamer's meltdown would be closer to 10.
- The meltdown explosion appears to carry any additional effects of the weapon that triggered it, such as igniting enemies, and any critical kill effects (enemies critical killed by a laser triggered meltdown become ash, while a plasma triggered meltdown produces piles of goo). This, along with the damage correlation, may indicate that the game treats any enemies struck by the explosion as if they were hit by the triggering weapon itself.
- The explosion caused by Meltdown is not affected by the Splash Damage perk.
- Only the initial hit of a weapon can trigger meltdown from killing an enemy. If a weapon has a damage-over-time effect (such as the flamer or holorifle), it will not trigger meltdown if it's the cause of an enemy's death. It also appears that the "bonus damage" of the pulse gun will not trigger meltdown.
- Weapons which fire in "bursts" in V.A.T.S. can trigger multiple explosions. If an enemy dies before the final shot in a burst each subsequent hit in that burst will cause another explosion.
- If Meltdown occurs with the Compliance Regulator, it's possible to freeze the Courier as well.
- verification overdue, remove As of the latest patch, Meltdown has a high chance of crashing your game.