In Greek superstition these are little demons or goblins that come on the earth for twelve days beginning on Christmas and ending their visit on Epiphany.  They are thought to not commit any major harm to humanity other than carrying on mischievous pranks.  The crimes that they commit are usually quite minor such as riding on a persons back, or extinguishing fires. Around this time period scratches on the walls or fire places are considered to foretell the presence of these little men.

As the Kalikatzaroi are demons in order to prevent them from entering a household during this twelve day period some people dip crosses into basil and holy water and sprinkle the rooms of their home.  It is believed that the Kalikatzaroi are fearful of  holy water and will not enter a house that is blessed.

The Kalikatzaroi are said to enter a house from the chimney in a similar manner as "Santa Claus", to prevent the Kalikatzaroi from entering a house during this period fire places are kept burning all day long.

The most notable story of the Kalikatzaroi is the "Story of the Tree of Life." The tree of life is considered as the base of the world, "The support which the world is build on" if the tree is cut down the world will come to an end. The Kalikatzaroi for the span of the whole year can be found chopping at the tree of life trying to cut it down and bring an end to the world.  When the Kalikatzaroi have almost succeeded in their task and the world stands on the support of merely a strand of wood  Christmas arrives.  The Kalikatzaroi then run up to the earth to cause their mischief.

The Kalikatzaroi arrive with their leader Koutsavli who rides on a crippled horse the day before Christmas.  When the Kalikatzaroi see the priest begin the blessing of the waters on Epiphany their mischief comes to an end as they run back to the depths of the earth in a panic.  When back in the depths of the earth they are shocked to find that the tree of life has replenished itself.  The Kalikatzaroi then begin the task of cutting down the tree once again, only to have the same thing happen to them year after year.

In the past Kalikatzaroi were used mostly as a fairy tale to scare little children.  Though they were considered to commit pranks such as messing up a house some of the pranks were not always bad.  In some areas of Greece nuts would be thrown into the houses only to be picked up by the children. Little pranks such as this and other weird occurrences were considered actions of these little men!