In the World of Warcraft community, there is a thing known as "Friendship Moose".
Right now, and soon to go away, everyone who gets the "Ahead of the Curve: The Black Gate" Achievement by participating in a kill of Archimonde (the final boss of Warlords of Draenor) also gets a quest item. Once the quest is complete, the player gains a Grove Warden mount; this is an enchant moose. The catch? You have to do the kill on Heroic Difficulty.
Lots of people want it, but lack either the time to put in the work, lack the desire to do so, or lack the ability to do so. So they seek other ways to get in on a kill. They can't properly contribute, so the rest of the raid group has to pick up the slack and carry them to victory. Hence, this is where "carry" became a noun; it refers to those who are present but cannot properly contribute to the group's success.
Normally carries are not desired. Temporary carry conditions--such as getting a raider's alternative character properly equipped--are allowed, as it is understood this will end swiftly and the former carry becomes a contributor instead of dead weight. Less common is someone paying the group to carry him, and often done when the content itself is well past its freshnessness for the better raiders, which raid groups do to refill their coffers for future expenses.
Friendship Moose is something unusual. It's some of the top-end raiders freely carrying people to the Moose and Achievement. Just show up, follow instructions, and enjoy your awesome moose mount.
And yeah, even though I'm not a Mythic raider I'm sufficiently powerful on my main character to help carry others to their Grove Wardens. This will also solve my own raiding frustrations--not enough Archimonde kills, so not enough shots at the best items I can get for my Fury Warrior main--as I help others get that moose.
And yeah, it's pretty sweet. Let me post a pic below:
This is one of the best things to happen in the World of Warcraft community is a while, and I can't wait to get in on this action. I hope to get the one Item Level point I need this weekend, after which I'll throw my name into the hat for being one of the DPS carriers. Win-wins are good things, and this? Totally win-win.