Old House, Grenade Launcher, Greenhouse
You'll remember this bridge from the Mia videotape. Where did Mrs. B even get all these dolls? Approach the door, and massacre some crates for some goodies (if you want, you can always nip back to the trailer to drop off excess goods- there's no penalty for waltzing between areas).
Enter the double doors to find the place has changed slightly since Mia was here. More bugs. There's just a few in the entryway here, but knife 'em anyway- they bite.
Retrace Mia's path. The tv room is now buggy rather than moldy, but just sprint past the Hive here. Those things are like bullet sponges.
Still following Mia's route, exit the tv room and turn left. Grab the map at the end of the corridor here, to your left just before the door.
Pass through the shadow room and grab the burner grip from the trash.
Rummage around here for other miscellaneous lootables, then go to the little shack at the end of the jetty.
This is a save spot, and it also has a backpack that extends your inventory- very handy and good for an achievement (In the Bag). There's also a Mr. Everywhere doll hiding amongst the beads.
Save and shuffle inventory, then return through the house (possibly slashing away a few larger bugs as you go) to enter a door you haven't been past yet- the one to the right of the tv room exit.
There's some solid fuel in the dresser, and a spider-covered cabinet in the corner. It's worth at achievement to knife away the spiders (Slash-Slash-Slashity-Slash!), but you're going to take damage doing it. Exit left, to a little outside area. Go around the corner for a spot of loot, then return and hasten past the hive, turning toward another little shack.
Inside you'll find some loot and the burner nozzle. Combine with the grip to make a genuine (if not exactly name-brand) flamethrower.
Ignore the hive again (ammo is precious, yo) and return to the save room to gear up for combat. You may consider returning to destroy the hive in the tv room- there's some ammo and healing components there that almost make for the ammo and health you're likely to expend taking down the hive, but it does make passing through that section later less of a hassle.
If you're trophy hunting, now is a good time to make a play for the 'Less is More,' and 'Back Off, Mrs. B!' achievements. Both involve wading into the Old House and expending ammo, so the save room here makes a dandy recovery point once you've bagged the achievement. Learn more at our achievement guide here.
Then, playing for realsies, go back to the room that leads out to the burner-nozzle dock, and turn right this time. There's a swarm in front of this door now- hose it down with fire, and do the same to the hive just beyond the door.
Beneath the charred remains of the hive is a tunnel leading downstairs. Leave the door a moment, and look to the small cart for an Antique Coin.
Now look behind you for a Mr. Everywhere wedged into a corner.
Proceed through the door for the spider Stone Statuette, and a bit of scripted dialogue, during which you're not allowed to shoot anybody
Back upstairs, the rules have changed. Marguerite is now hunting you, albeit not very well. Whatever door you try to leave by she'll slam in your face, then coat with spiders. Burn them away with short puffs of the flamethrower to continue.
The less swarmy path is actually the one past the still-intact hive in the room- sneaking under provokes way less aggression than going through the other door. This will take you back to the entry door, and now it's like a replay of the Mia footage (except you can stop off at a savepoint half way through).
Put the Stone Statuette on the spider plinth, and reaccess the passage here. It's gotten a little slimier and a lot leggier since our last visit.
Continuing the theme of 'things that doomed people in the videotapes are fine for Ethan,' drop down the same hole where Mia was discovered and dragged away screaming. There's actually a lot of good stuff down here, some chemfluid, a supply crate, the mechanical crank you need to further your mission, and even a Mr Everywhere figurine.
Scoop it all up, then emerge from the hole undragged. Use the crank with the metal apparatus here to raise a bridge across the gap in the house (you may need to slash a few flies in your way).
(You might also nip up the stairs while here to note the Crow Door, and grab some loot from the drawer. Plus the note here is a journal entry). This bridge connects back to the entry area of the house- your goal is to get back to that pier area where you found the burner nozzle. Speaking of which, equip the burner for this next section- you'll need a few puffs of flame to clear the wandering swarms. Marguerite tends to hang out in the Dining Room, with her attention focused on the northwest door, so your best bet is to approach from the Living Room (the room that had the fireplace access to the basement with Mia).
Wait until Marguerite wanders off toward her favorite door again, then sneak behind her and out to the water. Use the crank just the way you did before to access this last little shack. It's got lots of choice lootables, including burner fuel and a First Aid Med out front. There's also an Antique Coin on the toilet tank here (the Bakers sure have quite the toilet collection. Toilets and discarded riding mowers).
This shack also has the long presaged Crow Key, which you can use to enter Marguerite's altar on the second floor of the Old House. But first things first.
Recall another Crow door, back in the mansion Drawing Room, with all the stuffed hunting trophies. Sneak out of the Old House the way you came in (ie through the dining room), then sprint back to the trailer. Offload your gear, including the shotgun and/or burner- you won't need them for a bit. Pockets lightnened, re-enter the mansion.
There should be no hostiles there at the moment, so make yourself at home, maybe even rummage around some areas you feel you didn't properly search before. When ready, unlock the Crow Door.
There's a lot of ammo & supplies here, on shelves and fallen behind crates, but of course the big win is the grenade launcher.
Alas, there's so little ammo available right now it's not much use for the upcoming boss fight with Marguerite- but aren't you happier just knowing it's yours? Stop by trailer to swap out your gear, then head back to that other Crow Door.
Marguerite ambushes you and throws you down a hole, then stands at the top and throws bees at you. The key is to take her out before she starts spawning swarms- headshots with enhanced pistol ammo are ideal for this.
Just a few rounds will send her toppling into the pit- immediately start climbing the ladder out. Maguerite is about to become a big puddle of something toxic, and your skin has suffered enough trauma tonight (jk- it's in for so much more trauma). At the very least, you have access to the Crow Door now.
Explore this little altar area for some loot and, inside the case, the serum formula. Your watch says something about 'TARGET ACQUIRED,' but I'm sure that can only be good news. You get another call from Zoe at this point, and once again forget to ask her to give you an outside line.
She does tell you to finish exploring the second floor. There's not much square footage up here, but you will find Marguerite's journal stuffed into a room with an extraneous piano. Up a short flight of stairs is room with a lantern hanging from a scale, as well as a Mr Everywhere on the central table.
Turn around to claim an Antique Coin from the drawers in the corner.
Now pay attention to the scale itself, which is connected to the closed door.
Connected, one might note, BY STRING. Simple enough to adjust the scale to- no, wait. Even easier than that would be to chase a mutant murderbug lady into her deathtrap lair in the hopes that her lantern- which we keep shooting with shotgun blasts and liquid fire, somehow still weighs the same as this other, unshot lantern. So great when a plan comes together. Go back to the pit where you left melted Marguerite just in time to see her abscond with the lantern. Jump down in the pit and follow her into the tunnel, as Ethan continues to feel really good about this plan.
Luckily there's no danger here- the tunnel comes up in the courtyard to the greenhouse, with no hostiles about. Loot the area, but do not drop down to the lower level inside the Greenhouse. Instead walk up the hill to unlatch a gate to the trailer. Make sure you grabbed the Treasure Photo stuck against the Greenhouse entry.
This will give you access to a few Magnum rounds Zoe has hidden in her toilet. The safety implications are staggering. Return to the trailer to gear up for a fight, and save your game. Then it's back to the greenhouse and the lower level.
Loot and observe. There's a lot of material for both. When you've gotten both the goods and the lay of the land, go up the stairs to trigger an attack through the window.
This is a mere prelude to the main event, so don't waste your good ammo- even a few regular pistol bullets to the face will send her scurrying off. The rest of this section devolves into an extended game of cat and mouse. And as a wise man once said, there's only one way to win that game - don't be the mouse. Follow Marguerite as best you can, using the pistol when she's far away, and the the shotgun up close. The burner also does good damage, but try to keep a little fuel in reserve for vengeful swarms. Her vulnerable point seems to be the wasp factory in her gut (it does seem like that would sting), so concentrate fire there.
When she crawls out through an exterior window, heal and pick up the many supplies scattered about (there are some psychostimulants on the couch near where you came in that be quite a boon here). Also get ready to fend off a few bugs, which Marguerite generates whenever she's out of sight.
After that, it's just a matter of applying enough damage to bring her down. If you're having trouble with getting ambushed, try lurking in some of the lower rooms with limited access points. You'll have to fend off more bugs this way, but you'll generally get to fight Marguerite on your terms.
This is also a chance to get the Fly Swatter achievement for shooting Mrs B while she's leaping toward you. This is trickier than it sounds- her leaps are fast and the shotgun is slow, and has limited ammo. Best strategy is to lure her into the hallway at the bottom of the stairs. She really likes to climb up the wall to the second level and leap. Keep your shotgun ready and eventually you'll get lucky.
When Marguerite finally dies and disintegrates, pick the lantern from her scattered shards.
With the lantern in your hands, the bugspell is broken, and you can loot the place in peace. Replenish your supplies and get the hell out of here. The exit is near where you came in- it used to be barred by a grate, but Marguerite's death has dissolved its biomuck mortar.
Loot the drawer beyond, then head outside. Hit the trailer if you need to, otherwise you can head straight back to the Old House. Return to the lantern-balance room (no hostiles lurk between you and it), and appease the puzzle-spirits by hanging the lantern in its place.
The door opens, revealing a passage full of childrens toys and games- which are to scary houses as rattles are to snakes.
Still, you are in no immediate danger, so ignore the flickering lights and spooky warnings and even the room full of Mold as you make your way to a sinister bedroom at passage's end.
The dollhouse in the corner hides a map, which in turn reveals a secret passage behind the bed. Press through to discover a creepy but reasonably upbeat little shrine, with a mummified little girl slash mutant experiment at the end. Tear off the arm for your serum.
The screen may say '[F] OK,' but it really isn't.
Turn to catch a glimpse of a young girl scampering away, which is the scary house equivalent of rattling, hissing loudly, and rearing to strike. This time it's no bluff- there are a gaggle of Moldies between you and the exit now, but you can dash right past them, all the way to the phone.
Ringing phones seem to be their weakness, as once you pick up the phone, they stop hassling you (sonics & symbiotes, you know).
After the call, go downstairs and bid goodbye to this hellhole for that last time, heading for a rendezvous with Zoe at the trailer, with a new story achievement in tow (The Grave Will Out the Truth).