Halloween
The Halloween Event is a yearly event held from October 31st to November 6th. It was first added in 2021, and expanded on in 2022.
Like Talk Like a Pirate Day, Dr. Cubical will dress in a costume, appearing as a pumpkin, calling himself Dr. Pumpkical.
Halloween 2021
The first incarnation of the Halloween event was a simple quest board, with 9 total quests ranging from defeating a number of bosses in the Statue of Cubos to crafting a number of factory items, and completing all of them would award an Achievement and an Artifact.
As it was the first Halloween event, it was also very simple, and very easy to complete.
Halloween 2022
The second Halloween event in contrast, is much more complex. To even access it, you must be at least Military Tier 1. After that, clicking on the button that has appeared at the left-side of the screen, or the Ghost Ship near Shipyard, will take you to Halloween Island.
Halloween Island
Halloween Island is the main center of all things spooky. Dr. Pumpkical's spooky lair, the Spooky Tower, is where you will find the revamped quest system, along with upgrades needed to complete the event.
There are 3 main currencies: 
Pumpkins, 
Blood, and 
Souls. Each are used in their own section of the Spooky Tower to buy upgrades.
All three have differing ways to obtain: Pumpkins have a chance to spawn every time the wave counter changes and will bounce around the map for 30 seconds before disappearing. Clicking on them will reward you with pumpkins.
Blood must first be unlocked via a pumpkin upgrade to be collected. Once purchased enemies will drop blood on death as resources are.
Souls must also be unlocked via a pumpkin upgrade to be collected. Once purchased enemies will have a chance to drop souls on death. The change is based on modules with the #darkness tag equipped and can be upgraded with souls.
There are also three secondary resources: pumpkin brick (image), bats (image), and graves (image). All three are obtained three same way. All of them give a +0.01× resource (town, not event) boost per resource. All of them are unlocked at certain thresholds, and never spent.
Pumpkin bricks are used to upgrade the tower, and for the first column of assets. They have a formula of pumpkins >= 2 * 8bricks needed to unlock.
Bats are used to get grave stone town assets probably. They have a formula of blood >= 1000 * bats3 needed to unlock.
Graves are used to get the grave town assets. They have a formula of souls >= 50 * graves4 needed to unlock.
