Ok, there was a similar topic on B.net forums. Thought I would post one here. Here's the link to the original - Original Thread 
  
Rules 
  
Create a Skull, make a description of what it does, and say where it would be found in the Reach campaign. 
Multiple skulls are allowed. 
  
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Here's mine. 
  
Dodge This! 
All melee hits become an assassination, regardless of if it's from behind or not. 
Appears in the level Lone Wolf after you assassinate 100 enemies (in that mission). 
  
  
Be Creative! Ready? Go!