This is our proprietary skill rating calculation. This has nothing to do with official game ranking or MMR.
The purpose is to show player skill levels relative to other players, not estimate MMR.
PASSIVE - Basic Attacks against an enemy reduce your target's Physical Protection by 7% for 3 seconds (max. 4 Stacks).
PASSIVE - Your Critical Hits provide you with 10% Physical Penetration for 4s.
PASSIVE - Your Basic Attacks benefit from an additional 20% Physical Penetration.