Here are the official fastest time for clearing an instance or killing a Boss.

• Attumen the huntsmen 1 minutes 51 seconds [new record]
  
• Moroes 1 minutes 33 seconds
• Maiden 1 minute 0 seconds
• Wizard of Oz 2 minutes 28 seconds
• Romeo and Julliete 2 minutes 33 seconds
• Big Bad Wolf 2 minutes 49 seconds
  
• Nightbane 6 minutes 05 seconds
• The Curator 2 minutes 2 seconds
• Illhoof 1 minute 46 seconds
• Aran 2 minutes 11 seconds
• Netherspite 2 minutes 39 seconds
• Prince Malchezaar 3 minutes 2 seconds [new record]
  
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• Entire Karazhan instance clear in 1 hours and 52 minutes
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• Hydross 6 minutes 25 seconds
• Lurker 8 minutes 8 seconds
• Leotheras the Blind 7 minutes 44 seconds
• Fathom Lord Karathress 6 minutes 53 seconds

• Solarian in 5 minute 32 seconds
  

• Doom Lord Kazzak 1 minutes 6 seconds
• High King Maulgar 3 minutes 45 seconds
• Gruul 5 minutes 39 seconds
  

• Black Temple - High Warlord Naj'entus in 4 minutes and 30 seconds
• Black Temple - Supremus in 8 minutes and 40 seconds <<< NEW RECORD!
  
• Black Temple - Akama in 2 minutes and 5 seconds

• Mount Hyal - Kaz"rogal in 5 minutes and 14 Seconds
• Anatheron in 6 minutes and 22 seconds
• Rage Winterchill in 4 minutes and 12 seconds.
• Azgalor in7 minutes and 36 Seconds

Record times  need to be made  with an  officer in the group to verify the times made