Superman's famous heat vision, which he usually uses as a "utility power" for things like escaping something, freeing someone, or other uses. If he ever uses it as a weapon against an enemy, it's usually against a robotic or other nonliving enemy (because Superman adheres to Thou Shalt Not Kill). Him using this power is also usually a sign that you've truly pissed him off.
Superman (to Mongul): Burn.
- In the Silver Age, Superman had to wear glasses made from Kryptonian glass in order to use his heat vision while disguised as Clark Kent (otherwise the glasses would melt); Post-Crisis, this power was reinvented as pyrokinesis and thus that's not necessary anymore. Naturally, the TV versions tend to simply discreetly move his glasses out of the way.
- Originally, the heat effect was just supposed to be his X-Ray vision turned up full blast, so for most of the Silver Age it was always described as "using the heat of my X-ray vision." The phrase wasn't shortened to "heat vision" until almost the start of the Bronze Age. Post-Crisis, his heat vision has been considered a separate power from his X-Ray vision.
- Post-Crisis, Superman's use of heat vision changed markedly, as he was now a solar-powered superhero. Using heat vision came out of the same energy bank that all his other powers used, but at a very steep cost. Now heat vision was used sparingly or only once a battle. Really cutting loose with the beams now means that Supes is NOT in his happy place.
- Remember that bit in the cinematic trailer of DC Universe Online? He MELTED Black Adam's face off with only a guttural yell. Scene in question