The kallikantzaroi are evil goblins, found in Greek folklore, who live underground and saw the World Tree to try to collapse the earth. When Christmas season begins, they abandon their task to terrorize humans. On Epiphany, they return but the tree has healed itself.
Alchemist and Magician Edward Kelly, in the act of invoking a spirit of the dead at the churchyard of Walton Ledale, from “The book of black magic and of pacts” by A.E. Waite, 1898. The companion in the circle is likely Paul Waring, who helped him with all of his conjurations.