Shortly after getting washed up on shore during the Boardwalking dead story quest, you’ll automatically receive the Dez and the Mother of Satan side quest in Dead Island 2. The recommended level for this side quest is Level 23. For this quest, Hana will radio you. She needs you to look for Dez in the CDC Camp near the Pier. Make your way over there then speak with Dez on the roof of a dome building. She’ll ask your help in conducting her field experiment.
Next, she’ll set off her tests using chemicals in the area. She’ll call out which direction she’s going to set it off so stay clear! Fight off the remaining zombies. After the successful field test, speak with Dez. This time she wants some special innards from a zombie in the main dome. Head into the nearby white dome and loot the journal from the table.
Continue deeper into this structure. In the next room collect the Quartermaster’s Records.
In that same room, loot the Autophage: Vector Mechanics from the whiteboard.
Continue on the path. Eventually, you’ll use a keycard to enter the main dome. Inside you’ll find a bunch of zombies waiting for you. Take them all out including the electrifying Subject: Juliet. When you’ve achieved this task, speak with Dez to complete the quest. As a reward, you’ll receive 4,500 XP and Superior Melee Electrocutor Mod.