The woman had no tattoo on her arm before entering the flash. After she went in, she accidentally grazed her arm. She didn't care, but it didn't take long for the tattoo to start, and other players who were not injured also had it on their arms.
After moving on, we found that the soldiers who had died in front had this sign on their arms. They were all octopus, but this sign was not common in the army and was a common sign in ancient Greece.
The serpent is a snake with its tail biting. It is shaped like "∞" in mathematics, indicating infinity and cycle. The serpent is common in religion and mythology and rarely used in life. The serpent represents the eternal cycle of death and rebirth in religion.
Plato's evaluation of the snake is a primitive creature in the universe, with a perfect and immortal body, which conforms to the concept of the universe in the movie and represents the eternal cycle of life and death. The snake in the movie is also a physical concept.
In the movie, Josie found that there was no signal in the flash, but it was refracted by strange electromagnetic waves, so a large number of mutant animals and plants appeared. This concept is similar to Ouroborosaurus, which is reborn in destruction.
There is no real death in the flash, because of refraction, these animals and plants merge together, just like Josie, and become a plant. She didn't die, she just became a plant and continued to live. Everyone who stays in the flash has different degrees of variation, so this snake is the representative of death and rebirth. It is because of mastering this technology that aliens go to the earth to find new carriers.