Crimsonwood

Crimsonwood is an area in Masteria, and it's consisted of several parts: the Phantom Forest, Crimsonwood Mountain and Crimsonwood Keep (which is still closed at the moment).

In GMS, this area was introduced in August 2008 as part of v59 patch, and it was closed on several occasions. The Crimsonwood Keep Party Quest was introduced in March 2009, but it was removed in March 2016 as part of Masteria Through Time update, an update which was a reboot to the whole lore of Masteria.

With GLORY: Savior of Hope patch, which was released in late 2019, the area, along with New Leaf City, got entirely overhauled and has a new storyline, which is part of the major lore behind Masteria (with several links to Monad as well). This area is suited for level 180+ players.

Help Lita Lawless discover the dark secrets behind the Phantom Forest, where people are disappearing with no return, Meet the Raven Ninja clan of Crimsonwood, Uncover the last mysteries behind Masteria's history, and conquer the evil lurking in the forest to gain Blackgate Equipment and ShadowKnight coins, and lay your hands upon the most rare treasures of Masteria!

Sanity system

With the recent overhaul, this area features a new "sanity" system. As you venture longer and deeper through the creepy and harsh grounds of Masteria, the fears will start to overcome you, making you to slowly lose your mind and become insane. Losing your sanity will affect the player in several ways:

Your vision will fade from time to time, making you feel "dizzy".
Bizzare colors will cover your surrondings.
With low enough sanity, the screen will start shaking from time to time.
Decreasement in MaxHP and MaxMP, which will grow the less sanity you have.
Decreasement in EXP and drop rate, which will grow the less sanity you have.
Final Damage reduction, which will grow the less sanity you have.
With lesser and lesser sanity, the original background music of the map will fade, and will change to a darker one:
Several flying spectral creatures will start following you: Striking Phantom, Sad Phantom and Flying Phantom. They are barely visible at the beginning but they will become bolder the more your sanity decreases. If your sanity is low enough, the monsters will attack you by inflicting 10% HP damage and casting abnormal statuses on you. Several monsters casts potion lock, in a similar manner to Arcane River's anti-AFK mobs. However, the mobs here cannot be attacked, so they will stay until your sanity is restored.

The sanity system can cost many lives even to high-leveled veteran players, so be cautious. You can restore your sanity up to 3 times per day through talking to Garnet at Dead Man's Gorge. This is crucial, as most Phantom Forest daily quests will require a relatively long time to complete.