Big changes are coming to Dota 2 for Ranked Play in Dueling of Fates patch 7.07.
There is no more permanent MMR rating now there are 6 months long seasons where you earn Medals like Bronze Silver Gold Platinum Diamond Master & Grandmaster.
Each medal has 5 stars like divisions in lol or hots, for example, you can be Gold 2 rank and once you get to Gold 1 your next promotion is to Platinum rank.
We still don't know exactly the names and what MMR is represented to what division.
When the new season starts you will be able to recalibrate your Dota 2 rank after playing 10 games.
Your current historical MMR value will be recorded and selectable in your profile and ranked players will continue to be able to track their current seasonal MMR value. 
Your current medal, as well as your previous season's medal, will be displayed to all players before each match. 
We think the changes are great and it will mean that each player will have fresh rating and division.

The above changes to Dota 2 Ranked system are most important ones for us but there are other changes too with new heroes.

Two New Heroes are coming to the Hero Pool:
Pangolier is a Melee Carry with the following skills:
SWASHBUCKLE Pangolier dashes to a new position, assaulting enemies in the target direction with multiple quick thrusts, dealing physical damage and apply on-hit effects.
SHIELD CRASH Pangolier jumps in the air and slams back to the ground. Enemies around him are damaged and grant him temporary damage reduction the more heroes he hits.
HEARTPIERCER Pangolier reads his enemies perfectly, deftly slipping his blade past defenses to give his attacks a chance to slow the target and fully negate enemy armor after a short delay.
ROLLING THUNDER Pangolier curls into a magic-immune ball and thunders forward, damaging and stunning any enemies he hits. Shield Crash can also be used while this ability is active to jump over obstacles. Has a brief channeling period.
Dark Willow is a Ranged Support Nuker with the following skills:
BRAMBLE MAZE Dark Willow creates a maze of brambles that latch onto enemies who walk into a thicket, damaging them and applying a root.
SHADOW REALM Dark Willow recedes into the Shadow Realm, becoming untargetable and gaining increasing bonus magic damage for her next attack the longer she remains in the shadows.
CURSED CROWN Dark Willow bestows a cursed fae crown upon an enemy. After a four second delay, the target and any other enemies nearby are stunned.
BEDLAM Dark Willow's companion Jex circles around her, dealing damage to nearby enemies. Cannot be used while Terrorize is active.
TERRORIZE Dark Willow's companion Jex strikes fear into her enemies, causing them to run towards their home fountain. Cannot be used while Bedlam is active.
A new Dota 2 map mode is there as well called Turbo Mode.
In this mode, you will get more gold and experience to shorten the game.
Towers will be weaker too and All Pick rules apply, you will be able to buy items across the whole map.

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