Welcome to Treacherous Mansion E-2, Double Trouble. If you've been following our guide, there will be 4 Gem Stones that we recommend grabbing here that you haven't already found, as well as one Boo to track down.
Get things started by heading into the mansion. As soon as you enter the Front Entrance, there will be a gem you can collect. Use your Dark Light on the right gargoyle to reveal a chain. Pull it to cause the staircase to recede revealing a safe. Flash it with your strobe light to reveal a gem, but you'll have to take down a Slammer first. Once you have, use your vacuum to retrieve the mansion's 4th gem.
Okay, so in order to complete this mission, need to go activate a portal in each of the four corners of the mansion. While you can go about it in any order, we'll show you the fastest method, plus how to collect the gems along the way. Start off by heading right through the East Gallery into the Jungle Exhibit. If you try to free the Toad from the painting on the right side, a plant-monster will appear and that from happening. But we'll come back to this later since we need to go activate those portals first! Oh, and as for the ghosts, their spears are just like the shovels they wielded earlier in the game, so wait for them to attack before blinding them. Once they're down, continue past the monster plant and ride the dangling vine down to the lower level. Now head through the nearby waterfall to activate the first portal, which like all the other portals here, provides instant access to the Front Entrance. But we're not going to use it just yet.
Instead, head back through the waterfall and use the orange flower to spring back up to the level above, then continue through the northern door into the Grand East. But before we head through the door ahead, let's take a detour into the Restrooms down the left hall for a gem. But skip the first entrance, and instead use your Dark Light to reveal a second one just beyond. Inside, pull the flush chain on the toilet to reveal the mansion's 5th gem.
Now exit back into the hall, and go through that northern door we skipped a few moments ago--you know, the one with all the sand around it--which leads into the Ancient Exhibit. Step out onto the sand and use your strobe light to trigger both of statue's eyes, which will cause the sandy floor to sink. Once you reach ground-level, pull on the chain ahead to tear down the wall, revealing another portal. But before you can use it, some mummies will appear. While you can battle them like you have before, you can also lure them into the nearby torches to take care of their wrapping instantly. Once you've wrapped things up, activate the portal and head on through this time for a shortcut back to the Front Entrance.
So that's two portals down, and two more to go, both of which are on the west side. As such, head on through the left door and cross through the West Gallery into the Dark Age Exhibit. Interact with the metal storage closet to reveal a bucket that will come into play later, and some ghosts that you'll need to take down in order to open the chest in this room. Once you have, open the chest to find a...book? Place it back on the nearby bookshelf to reveal the room's portal. Activate it, then exit out the northeastern door.
Cross the Grand West to the door covered in snow and use your vacuum to clear it out of the way gaining entry into the Ice Age Exhibit. Before you go for the Portal, let's go for a gem. Tug on the woolly mammoth's trunk to have him launch you through the ceiling onto the roof. On the roof, you'll find some Stars in the in the shape of an even larger star, but it's missing three pieces. The first is right next to you--grab it, then launch it into one of the three slots, as marked by your crosshair. If you get it right, it'll take its proper place. But don't sweat it if you mis-aim, as another star will crash land so you can try again. Look for a second star in the southwest corner, caught in a gargoyle's mouth. Blind him with your strobe light to force him to release it, then launch it at the star in the sky. Now you might have noticed a star shooting by overhead--yup, that's the final one. Pull it down with your vacuum and use it to complete the sky star. For doing so, you'll be awarded with the mansion's 6th gem.
Now climb inside the nearby air duct to return downstairs. Head inside the igloo and activate the portal inside. Now that all the portals are open, it's time to solve some of those puzzles. Take the Igloo portal back to the front entrance, then take the closest one there to arrive back in the Dark Age Exhibit. Grab the bucket that should be lying around somewhere, then take the Portal back to the Front Entrance. Now warp through the far right portal to return to the Jungle Exhibit. Walk through the waterfall to fill your bucket, then use it to water the nearby plant along the north wall. This will cause it to grow a spiny bulb. Grab it, then bounce off the orange flower-spring to the floor above. Now fire that thorny ball at the plant monster to take him down. You can now finally cast your Dark Light on the Toad painting within to free the Toad.
But there's still one Toad left, but before we go save him, there's a gem you can now collect. Now you need to get to the level below, but because the Toad can't come with you on the vine, you're going to have to launch him over the railing to get him down there. After regrouping with Toad, grab the bucket and take it back through the portal to the Front Entrance. Then take the closest one back to the Ancient Exhibit. Proceed upstairs via the ramp on the right and then use your bucket to water the small plant by the palm trees. After it grows, flash it with your strobe light to make it blossom and reveal the mansion's 7th gem.
Now you'll want to return to the Jungle Exhibit for the next puzzle. And while you can take the nearby door through the Grand East hall connecting the two, you will have to battle some ghosts along the way. So it's actually easier to just take the portal again to the Front Entrance, then to the Jungle. This time, you'll want to grab one of the logs just left of the waterfall. Now take it back through the Portal and back into the Ancient Exhibit/ Use one of the lit torches to ignite the log, then carry it back through the portal to the Front Entrance again. But this time, head through the snowy one into the Ice Age Exhibit. Now use your burning log to melt the ice on the left side, where you'll find a Toad painting within. Shine your Dark Light on it to reveal a second Toad.
It's time to take them to the Inner Courtyard, but some ghosts will attack when you go for the door. After you take them down, exit via the door into the Grand West. Hang a right at the junction and exit out the far right door to reach the Inner Courtyard. Now E. Gadd's teleporter that you need to reach is upstairs, but there seems to be no way there...maybe that extremely suspicious looking statue in the middle has something to do with it! Try launching a Toad into both of the cages to find out. Upon doing so, this mission's Boo will appear and, in turn, make the statue disappear. Oh, and he's joined by some Sneakers too, who you should focus on taking down first Once it's just you and Boo left, you'll have to track him down and capture him in order to restore the statue.
Now tracking him can be tricky in a big area like this, but you can actually trick him into showing himself by attempting to restore the statue with the Dark Light and sucking up the spirit balls. This makes the battle a cinch. Once Boo's down for the count, reveal the statue for real this time. Now launch the Toads back into the cages to weight them down causing two light sensors to be revealed. Flash them both at the same time to cause a staircase to rise up from the ground. Climb it up to the teleporter to send the Toads to E. Gadd's lab and complete the mission!