While untying the stallion, he becomes scared and rather tantric. You
use an apple you had in your pocket to calm him down. You then find a
trail in the woods that will hopefully lead you and your new friend to
a cold stream.
The poor thing can't eat the grass around it and it is clearly
seen that the stallion has been neglected for days. You decide to
untie him and lead him to water and then use him as a means of
transportation.