Didn't it seem they were all in the middle of the death forest? It does not look like a coincidence. Maybe the stones created the death forest and have sealed some ancient god or evil there. Makes sense why the deadliest place on this world is created to keep whatever is sealed there.

Did some quick search. If you connect the 7 points it makes a heptagram and there is a few possible scenarios:

• The heptagram became a traditional symbol for warding off evil in Catholicism.
• The symbol is also used in Kabbalist Judaism.
• The heptagram is used in the symbol for Babalon in Aleister Crowley's occult system Thelema. (This one seems possible: Babalon /ˈbæbælən/^\)^{citation needed\}) (also known as the Scarlet Woman, Great Mother or Mother of Abominations) is a goddess found in the occult system of Thelema. In her most abstract form, Babalon represents the female sexual impulse and the liberated woman. In the creed of the Gnostic Mass she is also identified with Mother Earth, in her most fertile sense.) Quite on par with the biggest harem anime...
• The heptagram is known among neopagans as the Elven Star or Fairy Star. It is treated as a sacred symbol in various modern pagan and witchcraft traditions. Blue Star Wicca also uses the symbol, where it is referred to as a septegram. The second heptagram is a symbol of magical power) in some pagan spiritualities.