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 - For 8s after using an ability, your next Basic Attack will deal an additional 25% damage. Abilities that function like basic attacks do not benefit from this. PASSIVE - This item grants 2.5 MP5 per 10% of your missing Mana.
PASSIVE - You gain additional Magical Power and Lifesteal scaled from missing Health. This caps at 70 power and 10% Lifesteal at 40% Health.