To upgrade the Drillbreaker weapon in Final Fantasy XV, players will need to talk to Cid and get the A Better Drillbreaker quest. The quest will require Noctis to find a Magitek Core treasure item and give it to Cid for the upgrade.
While the Magitek Core is located inside the Zenautus Keep, the actual treasure item won’t be lootable until players have reached chapter 13. Players will have to unlock new areas in the keep by completing certain tasks. One such task is to gather security clearance levels for Noctis’ card.
A square storage room in the area with a tunnel has the Magitek Core in it. As soon as players enter the room, they need to turn right and the item should be easily visible. Alternatively, Magitek Core also had a 100% drop chance by defeating the imperial mech MA-X DUX. Killing MA-X Patria can also drop a core in rare circumstances.
If players are unable to find the Magitek Core in Final Fantasy XV through one of the above mentioned places, Gralea and Insomnia also have the item lying around in easily visible places. The sidequest Stealing the Past can also sometimes reward players with a Magitek Core.
Similar to other rare treasures, Magitek Core has a really high sale price and can be sold for 25,000 Gil so players will be tempted to earn that money but if they plan on ever using the Drillbreaker weapon, it is advisable to hold on to the core until they have acquired the upgrade from Cid.
Once players have Magitek Core in their inventory, they can return to Cid who can start working on the upgrade. The upgraded weapon should be available after a few days of questing and journeying around