Sickles???

It's a very rare axe... Where's the best place to get a max damage one to drop? Thanks

That's like asking where Crystaline Swords drop. Not every item in this game has a specific place for them to drop. In fact, a lot of the items are dropped in completely random places. The rarer items tend to be dropped from the higher level monsters though. All I can tell you is, if you want rare items, kill the high level monsters. ANY high level monsters. Don't ask me which ones, because I'm sure they all have about an equal chance of dropping them.