Euronotus is one of the Wind divine horses.
You can ride it over oceans to increase its wind strength or over mountains to increase its skills.
Rides over plains increase its skills and its wind strength.
Up until 3100 years old, as soon as the wind strength of Euronotus reaches 100 %, it'll be able to generate a storm.
Once the storm is over, you win one of these gifts: Philosopher's Stone
another surprise Wind direction determines skills points or wind strength that Euronotus earns during rides.
For a certain wind direction, Euronotus can also get a skills bonus or penalty for the current day.