Guild Wars 2 – Gadd's Last Gizmo

This is the fifth and final story mission for the Asura who chose the College of Statics. With the aid of Zojja you have recovered the Lab Key to the famed Genius, Gadd. Now you are to enter his lab. Head to the South from the Artergon Haven Waypoint. You will find the instance none too far away.

Once inside the instance head over to the East with Zojj and open up the door to the lab. At this attempt, a pair of golems will appear and attack you, Zojja and Mr. Sparkles. The 3 of you should have little trouble taking care of the golems.

When they go down head inside the now open doors after the cutscene:
Gadd: “Hello. If you are hearing this message, I'm either not in or dead. In either case, you're trespassing. Get out. Failure to comply may result in one or more of the following: blindness, crippling injury, severe bleeding, immolation, electrocution, death, and/or loss of appetite. Your agony may vary. You death may be monitored for quality assurance. Thank you. Now please run for your life and never come back.”
Zojja: “Same old Gadd, and his creations are still functioning after two centuries without maintenance. He was a cranky old cuss, but he built things to last.”
Hero: “Color me impressed … and a tad concerned. If his defenses are as sharp as he was, we'd better watch our step.”

Once through the entry door you have some flame walls to deal with. They flare up on approach so just time a roll through them after they flare up. With some good timing you can also just run right by it.

After the walls of fire have been braved it is time to face some electrocution. You have gates of electricity in front of you now. Gadd will appear again, taunt you, then disappear to have a pair of Sparks appear to attack you. Defeat them and more will appear. There are a good number overall. They will usually attack in pairs, with the odd single once in a while. You will notice that there is some scrap metal in the room. Grab a chuck of it and bring it over to the circuit. Interact with it to short it out with the scrap metal. Grab the second chuck and repeat this on the opposite side of the gate as well. This will short out the gate and stop the flood of Sparks coming at you. Making it through will just lead to another cutscene:
Gadd: “You think you're so clever, don't you. Getting this far is impressive, I'll give you that. But you're not out of danger yet. In this laboratory, I have harnessed unimaginable forces beyond your comprehension, and I'm about to unleash them on your face. Turn back now, or I'll enjoy desecrating your bones on my return. The pain you are about to experience will outlast your consciousness.”
Zojja: “The funny thing is, he's not even exaggerating yet. Still, if he's this determined to stop intruders, there must be something worth protecting here.”
Hero: “My thoughts exactly. I respect Gadd and all, but we've come too far to give up now. Sorry, old man: your secrets will be ours.”

Head into the room and activate the console in front of you. It will unleash a Destroyer Matriarch lvl. 12 and a number of Destroyer Hatchling as well, all lvl. 8. Use Area of Effect bursts to dealt with the Hatchlings, they are the easy ones. The Matriarch is the hard one. Pound away on it as much as possible as you deal with the hatchlings. It will take some time but it will be well worth the effort. There is one more cutscene in the lab:
Hero: “We made it. Gadd, you magnificent malcontent, we've got your number! And we've got this fascinating device Shrieksy found.”
Zojja: “Everything in Gadd's lab is worth studying. Tuck whatever that is away and we'll give it a good going over back at your lab.”
Hero: “Done. And am I crazy, or was that containment field holding back destroyers? That alone could revolutionize quasi-physical restraint field theory.”
Zojja: “You're not crazy, Savant. If we'd had those fields back when … well, let's just say more than a few battles might have turned out differently. This was a full-on, one hundred percent win. Not everyone can keep up with me … and most don't care to try. Ordinarily, that would suit me just fine. But you're all right. I'll definitely be calling you again soon. Now let's get that gadget back to your lab and examine the stuffing out of it.”

Leave the instance and return to your lab. That will conclude the College of Statics storyline. Claim your reward. You will get a letter from Zojja asking after your first invention to start the next storyline.