When in Goat MMO, you can hit
for a map of the area. You have to enter areas to "discover" them in MMO fashion, so use the map inside the spoiler for reference if you have not previously visited the mentioned locations in the following guide:
This achievement is gained in Alvesta at the northwestern end of the map.
At the lowest point of the area is an island with a wooden fence around its perimeter, and just north of this island is a sword in a stone by a tree.
You must lick the sword with
and then run away from the stone until it pops out. It's intentionally "stuck" in the level geometry and you have not successfully removed the sword until the achievement unlocks. I ended up at the center of the aforementioned small island before it came out.