1. On Metzen!
This achievement is very straightforward, although you will need to be at least level 40 to participate. This is because you earn the achievement by completing a seasonal quest entitled Metzen the Reindeer.
The Alliance version begins and ends with Wulmort Jinglepocket in Ironforge, while the Horde will need to seek out Kaymard Copperpinch in Orgrimmar. Metzen is located in two places, and either faction can save Metzen in either location.
In Tanaris, you will find the reindeer in a stable in the Lost Rigger Cove encampment. In the Searing Gorge, you can find him hanging out with some Dark Iron Dwarves near the tunnel to Loch Modan.
If you are around level 40, you may want to consider bringing a group along with you, although you should be able to run in and talk to Metzen, even if you die doing it.
In addition to the rewards for the quest, you will earn 500 reputation with the Steamwheedle Cartel.
2. With a Little Helper from My Friends
This is similar to the Hallow's End achievement, G.N.E.R.D. Rage, which required you to carry around a specific candy to eat after each death in a battleground in order to earn 50 honorable kills while the buff was active.
Unfortunately, this one might be a bit more complicated. You will find a curious machine outside of Orgrimmar and Ironforge during this event that can turn you into a gnome. In this disguise, you will need to earn 50 honorable kills.
As of Winter Veil 2007, the disguise did not last through death, so unless this is changed, you will have to come up with a way to earn many kill credits without dying, or enter an awful lot of battlegrounds.
In addition, druids might have some trouble given that in 2007, shapeshifting, which is necessary for a druid's survival in a battleground, broke the disguise.
This one will be fun and easy, as well as available to all levels. All you will need to do is obtain a snowball and then throw it at either King Magni Bronzebeard if you are Alliance, or Cairne Bloodhoof if you are Horde. Although there are several ways to obtain a snowball, they can be purchased from the Smokeywood Pastures vendors that will be hanging around major cities.
You will need to complete the quest, Bomb Them Again!, at the Skyguard Outpost linked to Ogri'la while mounted on a flying reindeer during the Feast of Winter Veil.
This one, unfortunately, will not be open to everyone. You will need to be at least level 70 and a flying mount, and to have completed the quest chains to unlock this daily quest. Check out our excellent guide to unlocking the Blade's Edge daily quests.
There will be plenty of death knights who are not attuned, so if you still need to do so, I recommend doing it in the first few days when everyone will be looking for groups.
As for the mounts, they may be added as either a permanent or temporary mount this year, much like the brooms during Hallow's End.
If not, the achievement can likely be earned by using Fresh Holly or Preserved Holly, although you might want to save your preserved ones, as they do not have a limited duration.
The holly will cost you! Put on your best lip gloss and get ready to /kiss some Winter Revelers. Eventually, you will get some holly from these jolly citizens, located in inns and other areas in the main cities.
5. 'Tis the Season
It is the season to get dressed up and gorge yourself on some Graccu's Mince Meat Fruitcake. Before you ponder what it might taste like, I recommend plugging your nose and wolfing it down. You should also wonder why you will need to be level 40 in order to handle it, or this achievement.
There are two ways to acquire this lovely treat, and one is to have completed the quest (and achievement!) to save Metzen the reindeer. The other is to bring some Treats for Greatfather Winter. Both quests will mail you a special something later.
The cookies for the quest can be purchased from other players, although you can also learn to make them yourself using a recipe that you can buy from the Smokeywood Pastures vendors. Even if you've never developed your cooking, all you will need is the skill point you are given when you sign up with your local chef, as this is a level 1 recipe.
The three pieces of holiday clothing will take a bit more work.
To begin, you will need to hire a professional Tailor. After all, you can't eat Mince Meat Fruitcake wearing nothing, and get an achievement, can you?
Horde Tailors can make Green Winter Clothes, while Alliance Tailors can make Red Winter Clothes. The recipes are occasionally seen on the neutral auction house, so if you fancy a specific color, you had best look around. If you are a Tailor, seek out the Smokeywood Pastures vendors in Ironforge and Orgrimmar for your pattern.
A Leatherworker will likewise need to acquire the pattern for Winter Boots.
The hats are somewhat trickier. Last year, they dropped from certain bosses in Outlands, although it is possible that in 2008, they will be found only on selected Northrend bosses. They also have a very small chance to drop from any humanoid.