Halloween n. (hal-uh-ween, -oh-een, hol-) 
- the evening of October 31; the eve of All Saints' Day; Allhallows Eve.
- celebrated by children going door to door while wearing costumes and asking for treats and threatening pranks.
On Gaia Online, Halloween (also known as H2K) was introduced in 2003 of October. A typical Halloween event on Gaia involves trick-or-treating by visiting Gaia Shops or Gaia Towns, the release of related items and participating in the sites main event. Halloween is considered a popular event for Gaians.
- During the month of October, Gaia begins to hype-up the coming events by releasing Autumn and Halloween themed items.
- Event related NPCs may make their presence known by posting in various forums, contacting Gaians through private messages, or making announcements about why they are on the site.
- Nearing the eve of Halloween, Shopkeeper NPCs are dressed in costumes and their shop interiors are decorated.
- During this time, Gaians can trick-or-treat to collect candy and then obtain items.