Hallowtide will be kicking off in ArcheAge starting on Tuesday, October 24th and running through Tuesday, November 7th. During Hallowtide, players can take part in a number of events including the search for treats, smashing pumpkins and battling the dead in both Two Crowns and the Solis Headlands. Doing so yields tokens that can be traded for a metric ton of stuff that includes cosmetic items, furniture, Merit Badges, Companions' Growthstones and more.
Also during the event, you can use credits to purchase the Stormwraith Kirin Crate that can contain items from Common rarity to Very Rare.
You can read up on all the fun on the ArcheAge site.