Chronologically a strange place to start. But I thought I would begin with a good one. My friend Bethpants hosts Halloween every year as a substitute for her birthday (because her birthday is on New Years and people are hard to group together on that date). She is the queen of decorating. What Einstein is to Science, Bethpants is to Party Themes.
Decoration
Dry branches and fake webs are effectively both foresty and doomy. Big focus on colours - black, red, white, brown. Plastic snakes and spiders are cheap and creepy. Bats are a must for a forest. Christmas decorations can double up as Halloween decorations once you drape some spider web on them. Frogs. Gravestones. My favourite effect is that from the decoration directly below - the black roses in the red liquid. I don't actually know what is in that liquid. I shall find out. It's probably just human blood.


DrinksWe made various coloured bowls of punch. Basic lazy punch can be done with cordial/koolaid, water and alcohol. This looks like various potions are the house. I like making fruit punch. I usually dump a bottle of champagne in a big bowl, with about 3-4 litres of Tropical Fruitjuice and some chopped up strawberries/pineapple/passionfruit. It often gets drunk very fast. Or if I'm lucky, I'll be amused by half-drunk people desperate for the last drops of alcohol drinking straight from the bowl at 1:30am in the morning. Bethpants likes to fill a glove with water and fut it in the freezer so that there is an ice hand shape for the punch to look creepy. Also, given the strangely indie and ironic society we live in - shaped ice cubes trays are relatively easy to find - so ice shapes like any of the animals dressed above would be perfect for a Forest of Doom party.
Games
We always play 'kiss-the-something' at Bethpants' parties. For the Forest of Doom, we played 'kiss the skeleton'. It is essentially an adult version of 'pin-the-tail-on-the-donkey'. We use (a preferably inexpensive) lipstick, and get lipsticked up good. The lipsticked person is blindfolded, and they then aim to kiss the, in this case, skeleton on the mouth. Closest to the mouth wins. We also played a Forest of Doom jeopardy style game. It had Halloween and Forest based questions. Instead of point categories, there were numbers of drinks people could allocate to others at their whim.
The Costumes
Because it was Halloween, there was no restrictions for costumes. I will now show you my friends. Some of them are most strange indeed.
Wizard of Oz: Mepants, Jesspants, Tompants, Sarpants.
Tinman's skin is just normal acryllic waterased paint. I used a fuelly car-type funnel for the hat. I have a heart pendant on my necklace, and the rest of the clothes are from the opshop (skirt spraypainted silver). I also had an axe! Scarecrow - flannelet shirt with faux hay in pockets, straw hat, jeans, boots. Dorothy made his entire costume. He is very good at sewing. I am jealous of this. The lion is made from a anime-style wig which was just smooshed out. All the lion parts were made from ripped up stuffed bear which was like $2 from an opshop. This would not be the last time a stuffed bear would die for costume. I think we did quite well.

Princess Leia: Scumpants
We totally constructed this costume. I am so proud. It was just a sleeveless white dress from the opshop. And we pulled a sheet through it to make a hood and made some makeshift sleeves out of the remaining sheet. Important must-haves: The hairdo and a lightersaber.
Pirate: Daniellepants.
This is a bought pirate costume. For your best pirate results add parrot and sword.
Cruella DeVille: Ninapants.
Must haves - Black and white wig. Some form of dalmation print. A stuff black and white dog. An evil laugh.

R. Patz: Tivpants.
This guy hates wearing costume. So R.Patz was perfect for him. Technically, he was "Edward Cullen" which means he dressed as a normal person, since that seems to be mostly what the vampires in Twilight are. He bought some vampire caps for his teeth. They were moderately expensive. He only used them once. Wearing caps is uncomfortable and slurry.
Yo Gabba Gabba Guy (DJ Lance Rock) and Bellatrix Lestrange: Pintopants, Bethpants (the host)
I THINK this is the Yo Gabba Gabba guy. Making Pintopants probably the first ever adult to dress up as him, and thus the coolest adult. Need - bright headress and thick frames. Bethpants is Bellatrix. She is wearing a massive black/white wig, had arm gloves and a fabulous corsette.