Lass is fine, his only good skill is Anal (Evil) Attack though. (In PvP)
And kunai+grab is lolhax if your opponent is clueless about how to counter it.
The map pieces (1-4) are used to buy crystal items in the shop. (Gorgos, Gaikoz, Partusay and Kamiki stuff)
And why they haven't released Kamiki weapons yet... I don't know,
Throw arrows upside down? O_O You mean rainstrom?