No one could actually remember seeing the sky burn. Not because no one was alive when it happened, but rather because anybody who had been outside when the planetary-wide combustion event occurred had been burned to a crisp within a few seconds.
In fact, a month after the event, when things had finally cooled down enough for the majority of the atmosphere to stop burning, most life on the planet had perished.
Without any animals off of which to feed, and any plants without which to replenish what little oxygen that had not been burned in the fires, whatever life survived the burn quickly perished, and all that remained from the oasis of life that had once been the Earth where a handful of cellular aquatic species that had lived in the depths of the oceans.
And yet as things cooled some more over centuries, that little bit of life that survived began to grow and adapt, and as the carbon heavy atmosphere settled, and the fires died down, new plants grew and propagated around the planet.
And life, as it had done so many times before, prospered on the earth, and the planet’s third great age finally began.