The Whispers Explained

Pursuing Adam: Head northwest then north in the Forest to find a gate. Use the key to enter. The Broodmother will attack, spawning smaller spiders. The Broodmother spits tentacles to drag you in. Use weapons like the Submachine Gun or Riot Shotgun and keep your distance. Avoid using explosives like Molotov Cocktails or Mining Explosives due to the Broodmother's movement. Defeating the Broodmother grants the 'That’s a hell of a spider' achievement. After the fight, you can complete the 'Full picture' achievement by finding all 41 locations on the map provided.

Exploring the tunnels: Head north from the spider battlefield to find a bunker entrance leading to tunnels. Follow the path, find a map, a TV save point, a campfire, and a note. Crouch and move west, fighting spiders. At a path split, head northwest to fight tentacle men and a hazmat enemy. Look for a locked door to the northeast and loot containers to the west. Head southwest and burn down an obstacle (Molotov Cocktail recommended). Follow the path, and at another split, head east. Crouch under supports, break another obstacle, and find a box. A door northeast of the box is a shortcut. Head southeast of the box, then east through an electrified area, defeating a large enemy and finding a first-aid kit. Northeast of the kit is a broken mine cart with a Minecart Brake Lever. A switch southeast of the cart deactivates the electrified zone. Head southwest of the cart, defeating a hazmat enemy and a tentacle man guarding two lootable containers. Return to the previous path split and head west. Fight a large enemy to reach a broken mine cart. Use the Minecart Brake Lever and Fuel to activate it, opening a door. Inside, find a Workbench, a TV save point, a note, and two containers. Use the cart to move to a previous area with a previously locked door to the north (now open). Follow the path, find a first-aid kit and a TV save point. Continue, fighting ambushing large spiders. At a path split, going northwest leads to a dead end with a large spider and two containers. Head northeast, fight a large enemy, and find a first-aid kit. Loot a box on your right. Beware of two tentacle men to the southeast and a large spider to the southwest at the next path split. Continue along either southern path, which merge. Defeat large spiders and find a trapdoor. Loot a box north of the trapdoor. A shortcut northwest of the trapdoor leads back. Go through the trapdoor, follow the path southeast, fight a large spider, and find a first-aid kit. At the path split east/west, head east to find a TV save point, a Crank on a machine, and a lootable box. Return to the split and head west, crouching under supports. Find two boxes near a ladder (a shortcut to the tunnel entrance). Return to the original ladder and go up. Head northeast, stick to the left wall, and find another ladder. Go up this ladder, fight a tentacle man, and loot a box southwest of the trapdoor. Head south of the trapdoor and follow the path.