To earn this achievement:
- Pick up the quest You're a Mean One... (A)/(H). Although it is a group quest, you do not need to be in a group. (Makes it easier, though.)
- Get to Hillsbrad Foothills. How you do accomplish this step is up to you.
- The The Abominable Greench's cave is in the southeast corner of the Ruins of Alterac sub-zone.
- Help kill the yeti or fly above and wait for him to die.
- Loot one of the sparkling presents.
- Speak to Metzen the Reindeer.
- Get back to Ironforge / Orgrimmar.
- Turn in quest. Receive achievement.