Lineage 101:
Maybe it's old news, but just today I found out that you can actually upgrade your little wolf fang's to even higher ranked weapons (all the way to basic fenrir weapon), that, AFAIK, you can't buy in any pet shop. The p.atk of the wolf gets to pretty high number that makes it somewhat viable to level with. At least for a little spoil like myself.
Go to pet manager -> Exchange pet equipment..
yea but this is expensive :)