Within Our Grasp

This achievement is easily obtainable under certain conditions:

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• The opposing faction must control WG
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• There can't be any horde players to kill your vehicles (try queing late at night)
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• There must be one or more other players to cap Sunken Ring (Broken Temple if you're horde) at the very beginning (have a friend que with you)
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As soon as you enter WG, head for the npc spawn points in the upper middle road, located around 49,51 and 48,42. Travel between them killing the enemy npcs, this is the fastest way I've found to rank up. The respawn times are fast, even if you one shot them and use mobility cooldowns the next set will respawn by the time you get there. It should take about five minutes to achieve [spell=55629] ranking. Once you do, run to Sunken Ring/Broken Temple that your raidmate capped earlier and grab a [npc=32627]. Head for the horde walls and start pounding away. If you did everything correctly, the clock should be around 21:30 by the time you destroy the fortress door and claim the titan artifact.

Yeah it's gotta be broken. We got it today after successfully defending Wintergrasp.

Goon Squad shows us how it's done