Real Life lava is molten rock. (The subterranean version is called magma.) Imagine an entire lake of electric-stove heating elements, all glowing red-hot. Its viscosity ranges from water-like fluidity to 100,000 times greater. It is an opaque emitter of reddish-yellow light. Its temperature is typically 700-1200 degrees C; coming within a dozen yards of it can inflict fatal burns. In many video games, lava is water recolored red with a damage script attached. (And sometimes the water causes just as much damage.) Acid and toxic waste will probably be Lemon-Lime and grape, respectively.