mythical era: i evolved into a stellar-level beast

Above the sky, a kilometer-long giant fish flew over the city, ignoring the bombardment of missiles.
In Australia, a kilometer-long world-destroying python destroyed cities, devouring millions of people, and slowly left under the explosion of several nuclear bombs.
Coming to this dangerous world, Jack Clark, who unexpectedly obtained a salamander clone, was a little confused.
What could he do with a palm-sized hexagonal salamander? Make videos to earn money? Catch shrimps in a stream? Or... make it evolve into a giant beast?
A hexagonal salamander, also known as a hexagonal dragon, with unlimited evolutionary abilities, gradually evolved into a mythical world-destroying beast. From a hundred meters long, it turned kilometers and tens of thousands of meters long...
And under the synchronized strengthening, Jack Clark's original body also grew stronger, with increasing strength and speed, and even...