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 - Your Basic Attacks deal +25 True Damage and your Abilities deal +35% Damage versus Jungle Monsters. When you kill a Jungle Monster you are restored for 10% of the Monster's Health and 25 Mana. Can be upgraded at level 20.
PASSIVE - You gain additional Magical Power and Lifesteal scaled from missing Health. This caps at 70 power and 10% Lifesteal at 40% Health.