Walking with Spirits

 is a Fallout 3 quest and achievement that is added to the game with the Point Lookout add-on.

Walkthrough
You receive this quest from Desmond after defending Calvert Mansion from Tribals, Desmond asks you to infiltrate the Tribals to found out why the Tribals are attacking Calvert Mansion. You are directed to the Ark & Dove Cathedral and talk over the intercom with one of the Tribals. After convincing him you want to join, he will send you on a test. He tells you to find the mother of the Punga plants and take her giant seeds.

Once inside the bog, you will fight through several mirelurks. When you take the seeds of the plant a gas sprays out from the fruit and your character falls over. When you awake, you experience a psychedelic hallucination. In other words, you start TRIPPING BALLS! You will find giant bobbleheads with cryptic messages written on them, arranging from expressing the PC's inner doubts and fears, to making fun of his/her misfortunes. You will be attacked by ghost Ghouls (that won't hurt you), journey through an upside-down swamp, and even find the skeleton of your dead mother (with a nearby bobblehead explaining that it would have wanted to die with you as a kid). You will find several dead bodies of people from the Capital Wasteland that disinegrate when searched, including Moira Brown, Amata, Elder Lyons, and an unnamed Settler, possibley the Megaton Settler who gives you items for having good karma. Finally you find the Megaton bomb with a character similar to Mister Burke standing in front of it. The Mister Burke character is actually the person who "frees your mind" but is seen as Burke. He warns you to take it easy before the bomb explodes and you awaken in front of the Sacred Bog.

When you return to the Ark & Dove Cathedral, you are permitted entry. If you enter third-person, you will notice that any headwear you had equipped is presently gone, and you have a large scar on your forehead. You will be unable to equip the headwear you were wearing until you have the scar removed by...Nadine! Apparently, she has joined the Tribals to procure their Punga, in failing to achieve her original goal of discovering treasure in Point Lookout.

Understanding the Visions
Later revealed that Tobar uses the time that a person is knocked out to lobotomize them in order to make them susceptible to becoming a member of the Point Lookout Tribe, some of the strange things that you see include a translucent saw cutting through the ground alongside the path, as well as later a threadlike object diving in and out of the earth along the path and then finally disappearing before the finale hallucination, can be interpreted as follows:


 * The saw cutting could be the moment when Tobar is opening your head/skull
 * ALL of the weird things may be when he is removing the brain tissue
 * The strange "thing" than "sews" it's way along the side of the path in front of you is when Tobar is sewing the wound shut.

Reward
Access into the Tribal's headquarters.