# 腐化地區 A **腐化地區** or **corrupted area** is a randomly-generated side area indicated by a glowing, beating heart and swirling ribbons of blood. Every corrupted area contains a boss, guarding a Vaal Vessel that drops Vaal Skill Gems, Vaal Fragments, and corrupted equipment. One Vaal skill gem is guaranteed to drop. Near the vessel there is a Vaal Letter or Research Journal, which provides Vaal-related lore. Corrupted areas have [[modifiers]], similar to end-game [[map]]s, which substantially increase their difficulty. Since corrupted items cannot be modified, the modifiers cannot be rerolled. Corrupted areas found in act zones spawn have 1 to 2 affixes (magic), while corrupted areas found in maps spawn with 4 to 6 affixes (rare). Due to the small size of corrupted areas, league mechanics are generally disabled from spawning in corrupted areas during challenge [[league]]s. [[Master]]s, more corrupted areas and Trials of [[Ascendancy]] also cannot spawn in corrupted areas. Notable exceptions which CAN spawn in them include [[Silver Coin]]s, Strongboxes, Shrines, Rogue exiles and [[Tormented Spirit]]s. Many of the corrupted area bosses were also formerly [Invasion bosses](Invasion_league).