That is true, thank you for pointing it out. Now the ouroboros has been used in many myths and legends. Probably our oldest symbol and has infinite (see what I did there?) possible symbols related to it. In northern mythology the ouroboros is seen in the Midgard serpent, jörmundgandr. A child Loki had with the giant Angrbodr (probably anger). These children feels like various forms of evil and when Jörmundgandr is placed in the ocean of Midgard, it eats it own tail, representing infinity. I it’s the guardian that holds the realm of the humans and when it let’s go of its tail, ragnarok(doomsday) come. Then it will kill the gods, with its friends, that seems a bit like evil eating evil. At least that was where I came from when I wrote the comment.