In order to activate Borderlands 2 Monster Mash Part 1, we have to speak to Zed in Sanctuary.
Zed wants us to collect some animal parts, no questions asked.
Dr. Zed is paying you to retrieve various creature parts for him.
You can get parts from any type of spiderant. He will not say why.
Item: Assault Rifle / Grenade
Experience: 3491 XP
After we activate the Borderlands 2 Monster Mash Part 1 mission from Zed, we have to travel to The Dust area.
Once in here, our objective is simple.
All we have to do is to go to the area behind Ellies Garage (Bug Gulch) and kill the first four spiderants we encounter.
Then we pick up the remaining parts they drop.
Now we need to go back to Zed in Sanctuary and turn in the mission to activate the next one in line, Monster Mash (Part 2).