VenomGems and a stick. The only mob seen holding a VenomBlade is when you challenge Herobrine for the third time. It deals 10 <3; enough to kill some things in one hit. For mobs that have higher health, the VenomBlade has a 85% chance to poison whatever it strikes, which causes a VenomBlade Poison effect. It can kill mobs if their health is low, unlike Cave Spider poison.
A VenomBlade is pure treasure and weaponary to all who hold it. It glows purple as if enchanted. It has twice the durability of Emerald tools (which have twice the durability of Diamond tools), meaning that the VenomBlade has 6248 uses.