Getting a Basket:
You must first buy a basket from Sally's Sweet Shop, found in the city, for $35. These restock 100 baskets every 15 minutes, so if you didn't get one yet, and it's sold out, just keep waiting and refreshing. This does not count toward your daily 100 item limit.

Earning Treats:
Any attack on any player can reward a treat. The default chance to loot candy from the first basket starts pretty low. This is improved by various basket upgrades as well as wearing "Spooky" clothing and having the finishing hit from a "Spooky" weapon (Assuming you have "I See Dead People" and "Here's Johnny!" unlocked on your basket).

Spooky Clothes:
Kabuki Mask
Medieval Helmet
Witch's Hat
Straitjacket
"Marauder Face Mask"
"Duke's Gimp Mask"
"Ginger Kid Mask"
"Scarred Man Mask"
"Psycho Clown Mask"
"Nun Mask"
"Donald Trump Mask '16"
"Michael Myers Mask '18"
"Gronch Mask '18"
"Jigsaw Mask '19"
"Pennywise Mask '20"

Spooky Weapons:
Axe
Blood Spattered Sickle
Chainsaw
Devil's Pitchfork
Golden Broomstick
Petrified Humerus
Wand of Destruction

Leveling up your Basket:
Your basket will "level up" to the next basket level automatically after you've collected the required amount of treats. It doesn't consume your treats to level up your basket. Each basket level improves the chance of looting candy by 5% per level (Up to +45% at Nightmarish).


Basket Levels:

Image	Name	Treat Cost	Total
	Spooky	0	0
	Creepy	5	5
	Freaky	10	15
	Frightful	25	40
	Haunting	50	90
	Shocking	100	190
	Terrifying	250	440
	Horrifying	500	940
	Petrifying	1,000	1,940
	Nightmarish	2,500	4,440

Upgrading your basket:
You can upgrade your basket to provide additional perks like higher drop chances, improved candy rewards, etc. It does consume your treats to unlock additional basket perks. You can do this by finding your basket under "Special Items", and clicking the "Use Item" next to your basket.


Basket Upgrades:

Image	Upgrade	Description	Treat Cost	Total Cost
Tier 1
	I See Dead People	This upgrade gives +10% chance of receiving a treat when wearing any scary clothing I.e. Kabuki Mask, Medieval Helmet, Witch's Hat, Straitjacket & Scary masks	3	3
	Here's Johnny	This upgrade gives +10% chance of receiving a treat when ending a victim with a scary weapon I.e. Axe, Chainsaw, Blood Spattered Sickle, Devil's Pitchfork, Petrified Humerus	5	8
	Doubler	This upgrade has a 20% chance of doubling the treats received after an attack This 2x bonus can stack with Tripler, Quadrupler & Quintupler	25	33
	Tripler	This upgrade has a 10% chance of tripling the treats received after an attack This 3x bonus stack with Doubler, Quadrupler & Quintupler	50	83
	Quadrupler	This upgrade has a 5% chance of quadrupling the treats received after an attack This x4 bonus can stack with Doubler, Tripler & Quintupler	75	158
	Quintupler	This upgrade has a 1% chance of quintupling the treats received after an attack This x5 bonus can stack with Doubler, Tripler & Quadrupler	100	258
Cumulative Total:	258
Tier 2 (Unlocks at Frightful Basket)
	Candyman	This upgrade unlocks medium-tier candy. Bag of Bloody Eyeballs is added to the candy reward pool.	5	5
	Sweet Release	This upgrade unlocks high-tier candy. Bag of Chocolate Truffles is added to the candy reward pool.	10	15
	Bloody Mary	This upgrade unlocks medium-tier alcohol. Bottle of Wicked Witch is added to the alcohol reward pool.	15	30
	Nice Chianti	This upgrade unlocks high-tier alcohol. Bottle of Stinky Swamp Punch is added to the alcohol reward pool.	30	60
	Nightcrawler	This upgrade unlocks medium-tier energy drink. Can of Munster is added to the energy drink reward pool.	45	105
	It's Alive	This upgrade unlocks high-tier energy drink. Can of Red Cow is added to the energy drink reward pool.	90	195
Cumulative Total:	453
Tier 3 (Unlocks at Shocking Basket)
	Cat in Hell	This upgrade gives a 1 in 500,000 chance with every attack of instantly receiving 1,000 treats. Or the equivalent of being struck by lightning...	13	13
	Save Your Tears	When exchanging your treats you'll also receive +500 happiness for every treat exchanged. Up to 99,999 happiness.	95	108
	Freebie	Receive an additional bonus treat for every 10 upon exchange. Exchange ten and get one free.	120	228
	Cold Sweat	When exchanging your treats you'll also receive +1 nerve for every treat exchanged. Up to 32,767 nerve.	170	398
	Cashback	After exchanging your treats you'll immediately receive 10% back with this upgrade. We want to reward your loyalty.	230	628
	Dark Power	When exchanging your treats you'll also receive +5 energy for every treat exchanged. Up to 1,000 energy.	285	913
Cumulative Total:	1,366
Tier 4 (Unlocks at Horrifying Basket)
	Multipack	This upgrade gives a 3% chance of consumables being upgraded to Multipacks upon exchange. I.e. A rewarded bottle of beer may become a Six Pack of Alcohol.	180	180
	Deal with the Devil	This upgrade gives a 3% chance of consumables being upgraded to Boosters and Special items upon exchange. Treats may be converted into Erotic DVDs, Feathery Hotel Coupons, Business Class Tickets and Casino Passes.	320	500
	Mortal Coil	Receive 1 treat for free every hour while the Halloween Basket event is active. A trickle of treats for doing absolutely nothing.	500	1,000
	Inflation	The treats in your basket increase by 0.1% per hour while the Halloween Basket event is active. This covers the rate of Freddo price increases and confectionary shrinkage.	777	1,777
	Shadow of Doubt	This upgrade immediately provides exactly 1,100 treats. Probably...?	1,000	2,777
	Summon Cthulhu	Begins the end times. It was nice knowing you.	9,999	12,776
Cumulative Total:	14,142

Exchange All Treats:
Immediately exchange all available treats for Candy and Drinks (Alcohol and Energy). This WILL consume any and all available treats you have at the time. This can be upgraded to get the higher tier consumables through basket upgrades.

Honors:
 Phantastic - Upgrade your Halloween Basket to Frightful
 Something Humerus - Upgrade your Halloween Basket to Terrifying
Oh My Gourd! - Upgrade your Halloween Basket to Nightmarish

FAQ

When does the Halloween Trick or Treat event start?
The event technically starts on October 27th, at 12:00 Torn City Time - However, this is purely for the start of baskets appearing in Sally's Sweet Shop. You can't actually loot treats until 14:00 Torn City Time. The event ends on November 3rd, at 12:00 TCT.

Do your treats carry over from last year/into next year?
Yes! So if you want to keep upgrading your basket, don't "Exchange All Treats" at the end of the year and save them for next year!

Does it cost treats to level up your basket?
No. Think of it like a progress bar - Once you've earned the required amount of treats (spent or unspent), the basket will "level up" automatically to the next level.

Do upgrades carry over between baskets?
Yes. If you have one basket and unlock a bunch of upgrades, and your basket "level's up", your upgrades will persist onto your new basket.

Which upgrades are best?
This is mostly up to player opinion, however, I'd recommend unlocking all of the Tier 1 upgrades first, and then skip Tier 2, and start unlocking Tier 3 upgrades. Tier 2 upgrades are only useful to "Cash out" your treats, which...if you're in it for the long term, won't be until after you fully upgrade the basket anyway.
Andyman breaks it down further here

What does "Summon Cthulhu" do?
Good question. Nobody knows. Let me know if you want to be the first one to throw 9,999 treats into a pit of despair and find out though!

What does "Exchange All Treats" do?
This will consume all of your available treats (seen in the top left corner of the basket interface) for various items like candy, energy drinks, and alcohol items. You can upgrade these rewards in the Tier 2 section of the basket, and again in the Tier 4 section of the basket to even get things like Feathery Hotel Coupons, Erotic DVD's, and Lottery Vouchers.
Note: THIS WILL CONSUME YOUR TREATS. This will use all the treats you have saved up for upgrading your basket. I suggest doing this AFTER you've finished upgrading your basket entirely.

Can you earn treats from defends?
No. You only earn treats from attacks you initiate.