Lostlorn Forest (Japanese: 迷いの森Bewilder Forest) is a small forest in the middle of Unova. It is connected to Route 16 in the south, and is home to a female Zoroark.
During the first visit to Lostlorn Forest in Pokémon Black and White, there is a Backpacker standing in front of a mobile trailer. If talked to, he talks about the woman living in the mobile trailer who thinks living by herself quietly is more important than traveling around the world like he does, before he leaves. The mysterious woman inside the trailer can be interacted with, but won't say a word to the player.
In order to catch Zoroark, the player will need one of the Shiny Legendary beasts to activate a special in-game event. Approaching the trailer in Lostlorn Forest with one of the Shiny Legendary beasts in the party will initiate the event, causing the mysterious, silent woman to emerge from the trailer with a screeching growl and attack the player.
When the battle starts, the player will suddenly face one of the normal-colored Legendary beasts that has a type advantage against the Shiny legendary beast in the player's party (In case that the player has the Shiny Raikou, Entei will appear.). Once the non-Shiny Legendary beast receives damage, the illusion will dissipate, revealing Zoroark.
After the player catches or defeats Zoroark, the true expanse of Lostlorn Forest is revealed, and the same Backpacker reappears and becomes surprised that the suspicious woman was really a Zoroark in disguise, who was only protecting her home by deceiving both people and Pokémon using illusions. He then states that Zoroark reacted strongly to the Shiny Legendary beast in the player's party, and assumed that she may have been in some sort of a previous conflict with it. In Black 2 and White 2, there is a Backpacker who speaks to the player about the Zoroark who lived in the forest, and gives out TM95 (Snarl), which was locked behind an unreleased event in Black and White. However, he is actually a Zoroark in disguise. The event may not work if the player has a Legendary beast from a foreign country.
Lostlorn Forest is an ordinary, small dead-end area inside the central forests of Unova, which contradicts the rumors that people get lost there easily. In Black and White, once the player catches or defeats Zoroark, the dead-end area is revealed to be an illusion, and Lostlorn Forest is shown to be a more wide open, windswept plain.
Despite Zoroark being able to be either gender and that it is more likely to be male, the Zoroark found here is always female. This is likely a reference to the female Zoroark that appeared in Zoroark: Master of Illusions.
In Black and White, Lostlorn Forest is the only location where the chance of Audino appearing in rustling grass is less than 50%.
Lostlorn Forest's waterfall is the only waterfall that can be climbed in Black and White before defeating Ghetsis.
Lostlorn Forest is one of two forests to only have one entrance, the other being Berry Forest.