My theory is that this video is about the loss of innocence in war-time or something similar. The monster is a figment of the boy's imagination and thus representing his innocence. The dogs and the hunters are representative of the violence he has seen and been a part of. Finally, these hunters wound the monster and although the boy tries to help the monster along, he must leave him, i.e his innocence behind and the hardened look on the boy's face as he ascends the summit is the boy sans his innocence. 
hablo españolxd