This post was from a user who has deleted their account.
For me it has to be What a Long, Strange Trip It's Been. Over the few realms I have played on I never had enough patience to do this, but once I started my current main and started collecting pets and mounts, I knew I had to have that lovely purple drake. It's the most feminine colored drake and it goes well with my little Paladin :-D
Mine is probably Friend or Fowl, people under estimate those little suckers! After having massacred most of the turkey population in the vicinity i was amazed by the turkeys teamwork and perserverance to take me down! Anyways it's my favorite and most proud of it because it's just really funny and i found the exact place in the world to do it without reading from any website or asking anyone :D
My favorite definitely has to be "What a Long Strange Trip it's Been". Not only did it give me the awesome Violet Proto, but it also gave me 310% flight speed. The achievement means even more to me because I missed out on one part of the Merry Maker achievement which caused me to have to wait an entire year longer than I had expected to get my drake. Now it's my primary mount and many people ask how I got it. When I tell them what all goes into doing all the holiday quests, they tend to decide that mount isn't for them, haha =)
I think the one of the great achivements i have is the The Safety Dance (25 player), its was a bit hard to get 25 ppl to not get hit ><
Mine is definitely Insane in the Membrane. It was such a long grind to get it, but well worth it in the end. My whole guild was behind me and supporting me and they cheered me on as I turned in that final Darkmoon Faire deck to get the achievement. And I had to get my name tied to the guild Dire Maul achievement because of how big of a grind it was to get the title!
I have to say Hot Streak, because i remember getting that by basically soloing the two opponents because my friend couldn't PvP for beans :(
im most proud of my thunderfury and sulfuras achievements, and if i could get my guild doing ICCs i could finish my shadowmourne too!
my Most proud achievement would be Insane in the Membrane. I must really be insane to actually go for the achievement. :)
The achievement I am most proud of is the because of how long it took for me to get it.
I earned the feat of strength, sergeant. I'm not talking about the extended arena sergeant, I'm talking about the vanilla, standing on top of a (small) mound of corpses sergeant.
I absolutely love hunting down rarespawn mobs. Not for loot, not for achievements, but just to see them and ...well enjoy it! I even take screenshots of all the Kalimdor and Azeroth rares that I find as well. So my answer is definitely Frostbitten and Bloody Rare.