Serpent's Wand it's the first weapon of the class Rare in which one can graph, or as an event reward, and as a random drop, for the class Wand.
About Serpent's Wand[]
A wand designed to be extremely offensive with great venom damage, plus the fact that it has a critical 1% chance and 5% critical damage when hit. Apparently it seems to have enough attack power for this rare weapon class, but since there are many monsters and machines with high resistance to poison, this makes the weapon ineffective against these attacks, but for heroes with little defense in the poison resistance , it becomes an excellent weapon for lower levels. Warlock seems to be the most effective weapon, even more combined with shadow attacks for much more effective damage.
Anyway, if you do not have a level high enough to graph larger damage weapons to Fiery Death or above it, then it is highly recommended to have Serpent's Wand if you work with high venom damage.