Confront the Source is the final mission of Gloomy Manor in the Dark Moon Quest in Luigi’s Mansion 2 HD on the Nintendo Switch. The whole mission takes place in the cellar and is a fight against Gloomy Manor’s final boss, a giant, possessed spider.
To defeat the spider boss, you have to use fire to burn its webs, but it’s not at all obvious how to actually do that. It also gets more difficult to burn the webs at each stage of the fight. I was left scratching my head a couple of times during this one, but eventually, I figured it out and defeated the spider boss. You can complete Confront the Source using this mini Luigi’s Mansion 2 HD walkthrough.
How to defeat the spider boss and complete Confront the Source in Luigi’s Mansion 2 HD
Suck up any red spiders wandering around, then go to the huge web at the end of the cellar and use your Poltergust 5000 to pull on the web ball. This will trigger the spider boss’ dramatic entrance and start the first phase of the fight. This will be a test of the spider web burning skills you practiced in the Sticky Situation mission.
Approach the spider boss, dodging its venomous spit and sucking up any more red spiders that appear. When you get close, the spider boss opens its eyes and tries to attack you. The instant it opens its eyes, tap A to dazzle it with the Strobulb. Then, walk under it and grab the web ball again. Pull it all the way over to the suit of armor on the left, trigger the armor’s attack, then move out of the way and light the web ball using the armor’s torch. This burns the first web and reveals the body snatcher ghost. Wait for the body snatcher ghost to charge at you, then move out of the way and stun it using the Strobulb. Then suck it up, pull it, and tap A to send it back to the spider boss.
Run behind the stairs to avoid the spider boss as it charges along the Cellar, then go back to the middle and point the Poltergust 5000 at the chandelier above. Hold suck or blow to make the chandelier spin, and keep it spinning until it has lit the brown web ball and burned away the large web on the right side of the cellar. This reveals a suit or armor with a long pike.
Now, the difficult part. Approach the spider boss, stun it, and grab the web ball, just as you did during the first phase. This time, the web ball won’t stretch as far as the armor with a torch, so instead you need to trigger the pike armor’s attack so that it impales the web ball (and ideally not you, too). On my first couple of attempts, the pike got me and not the ball, but eventually, I got the ball impaled on the end of the pike. Make the chandelier spin again—this time until it ignites the web ball on the end of the pike. This burns the spider boss’ next web and reveals the body snatcher ghost again. Deal with it the same way as before.
Run back to the stairs to avoid another spider boss charge, then approach the spider boss again. This time there’s a loose web ball right in front of it. Pick that up with your Poltergust 5000 and carry it back to the armor with a torch—this requires a lot of careful dodging. Light the web ball on the torch and carry it back the way you came. The walk back is easier as you can use the flaming web ball to kill the red spiders. Use it to burn the webs covering the armor on the left side in front of the spider boss, then stun the spider boss and grab the web ball behind it. Pull this to the armor on the left to light it and burn away the final web. Suck up the body snatcher ghost one more time to beat the spider boss, which will then revert to its natural, friendly-spider form.
This completes the Confront the Source mission and the Gloomy Manor section of the game, earning you a Dark Moon Fragment, and unlocking the Haunted Towers location.