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 additional Magical Power and Lifesteal scaled from missing Health. This caps at 70 power and 10% Lifesteal at 40% Health.
PASSIVE - When you take Magical Damage from Abilities your cooldowns are reduced by 3s. This can only occur once every 30s.