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 - You gain Physical Power equal to 2% of your Maximum Mana.
PASSIVE - Your Critical Hits provide you with 10% Physical Penetration for 4s.
PASSIVE - Enemies hit by your Critical Strikes have 40% reduced healing for 5s.
PASSIVE - When critically striking an enemy, gain a stack of 5 Physical Power, max 3 stacks, for 5s.