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 - While below 60% Health, you gain an additional 15% Physical Lifesteal for 5 seconds. Can only occur once every 15 seconds.
PASSIVE - Critical Strike bonus damage dealt is increased by 25%.
PASSIVE - When critically striking an enemy, gain a stack of 5 Physical Power, max 3 stacks, for 5s.