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 - This item grants 2 MP5 per 10% of your missing Mana. Your damaging abilities deal an extra 15 true damage to minions. Can be upgraded at level 20.
PASSIVE - Enemies hit by your abilities have 40% reduced healing for 5 seconds.