A cloaked-traveller speaks to you about a big favor. Eliminate 5 Sand Guardians in the Village of Vatir.
First, you must travel to the Village of Vatir. There, asking for the whereabouts of the Sand Guardians or simply listening to the civilians talk will reveal that the Sand Guardians are located in the southern part of the village. One or two guardians will, however not be present during the first battle. The remaining guardians can be found in a dungeon. They are stronger than the ones from the first fight.
Inside the dungeon, a gate will prevent you from entering unless you say "Makankasapatu". After this, the final fight of the quest can begin.
The Sand Guardians can easily be defeated with water based attacks. If you don't have a water attack, you can still throw a water bottle or brute force to take them out.
The Final Sand Guardians, however cannot be defeated by simply throwing a water item or trying to turn them into glass.
A spell was put on the Sand Guardians according to some civilians, suggesting they aren't naturally hostile.