Ok, this is a little late to post this, but I really didn't want Blizzard finding out about this and then fixing it T_T;;... (and again, didn't see a post on this, sorry if it's a repost)
Step 1: Wait until July 4th.
Step 2: Grab an empty cup from the tables near the holiday "Free-booze" kegs.
Step 3: Fill said cup up.
Step 4: Grab another empty cup and fill, repeat until you reach desired amount.
First, let me clarify on a bug there. You are not allowed to have more then one filled mug.. but you can have a filled mug and an empty mug, and I may be wrong on this, but i think you can have multiple empty mugs as well. The game never fails you on filling an empty mug just because you have one already filled, so 1 filled mug and 20 empty mugs becomes 21 filled mugs, etc.
Step 5: Walk to a mailbox.
Step 6: Mail every freakin' mug to your bank alt.
Step 7: Enjoy a mug during Christmas, and benefit from the slow fall at any time.
The mugs won't disappear in the mailbox, but they will keep their 24 hour deadline debuff, so as soon as you pull it out, the clock is ticking down. Use it, and before you empty it out, mail it off again, it resets the mug's fills. I still have about 20 mugs in bank, and as a lock, it's really nice to have an anytime use slowfall. I use it in instances like BRD all the time where I can chug it, pass it to another party member, and we can jump down skipping areas, slow fall for the whole party !
NOTE: IT RESETS THE DRINK'S FILL AMOUNT BUT NOT THE TIMER! if you hold it for 20 out of the 24 hours, then mail it off, next time you pull it out it will only have 4 hours on it, so I'd get a lot of them. ALSO, remember how I said you can't have more then 1 filled mug? Well, now it works as intended. You can't grab more then 1 cup from your mailbox at any given time, you have to grab it and use that one, or pass to someone else and have them pass it back once you empty the one on you. Once the cup is empty, it's useless unless someone else knows something it could be used for.
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Some helpful uses of this?
1. Instance area skippings (jump from the fire boss's circle room to the lava below in BRD, and skip quickly to the last boss area by sticking to the walls, avoiding the lava with the slow fall!)
2. Profit. (I can think of a few over-gold-filled twinks who would love to get one of these mugs for a hard day of AB grinding.. great way to take BS from LM.. and it's not soulbound, and counts as a conjured item, so they may be able to share it cross server for mass drunk attacks from LM?)
3. Fun for yourself (I find all kinds of excuses to use this, and unlike slowfall, you can mount right after chugging for extra distance jumps!)
4. To get to the Ironforge Airport (No need to be a mage, just chug this puppy, and run off the highest East most point outside the IF gates, aim for the break in the cliffs next to you, and explore the hidden Airport! See the fighting troggs, the useless FP, the airplanes.. then chug that puppy, mount, ride off in the direction of Wetlands, and see the secret farm hidden in the hills! You can chug while floating, for prolonged floating time!)