Mechanics

The Mechanics of Dota 2 describe the inner workings of the game. These are elements that are not required to play or even play well, but will improve a player's understanding of Dota 2 and provide them with more streamlined play. This article and the articles it links to describe more intricate elements of Dota 2 and are written for new and experienced players alike.

Engine
Dota 2 runs on a new version of the Source Engine. This version builds upon features introduced with Portal 2 and the Orange Box versions of the engine, such as flowmaps and advanced particle rendering, by adding features such as improved spectator support and cloth physics. Dota 2 supports a matchmaking system and up to 10 players in game at one time, but allows for large numbers of spectators in any given game.

Heroes
Heroes are all unique characters within Dota 2. At the start of each game, players are split into two teams of 5 versus 5 and then select a Hero from the Hero Pool. Every player controls his own Hero and any units that Hero controls, such as a Neutral Creep under the effects of Chen's Holy Persuasion.

Heroes will gain experience when enemy units are killed nearby. They start the game at level one, and as they earn experience, will eventually level up. Each level a Hero earns will increase their Attributes and learn new Skills.

Skills
All Heroes have four or more Skills, with one of those skills being their Ultimate ability. Every time a Hero levels up, they earn a point that they can place into ranking up any available skill. Not all skills will be able to have ranks placed in them at every level. The table at the right shows when ranks can be earned.

Attributes
In addition to unique skills and abilities, every Hero has a different set of Attributes which control their initial statistics. These Attributes are Strength, Agility, and Intelligence. In addition to bonuses earned by each Attribute, Heroes also have a "main" Attribute. Every point in their main attribute adds 1 to their physical attack damage. Typically, this will also be the highest Attribute at first level, and the one that receives the greatest increase as a Hero levels up.

Every point in Strength will... Every point in Agility will... Every point in Intelligence will...
 * Increase the Hero's maximum Health by 19.
 * Increase the Health regeneration of the Hero by 0.03 Health per second.
 * Increase the damage of Strength based Heroes by 1.
 * Increase the Hero's Armor by 0.14 points.
 * Increase the Hero's Attack Speed by 1 point.
 * Increase the damage of Agility based Heroes by 1.
 * Increase the Hero's maximum Mana by 13.
 * Increase the Mana regeneration of the Hero by 0.04 Mana per second.
 * Increase the damage of Intelligence based Heroes by 1.

Heroes will earn additional attributes whenever they level up, but can also receive bonuses and penalties from Items and some Skills.

Experience
In order to level up, Heroes must earn Experience. When a unit dies in Dota, it gives experience to all Heroes in a 1200 AoE based on its level. Experience is split among all Heroes in the AoE. If a Hero is killed more than 1200 units away from their killer, the killer still gains a share of Experience. Allied unit deaths do not grant Experience.

Denied units will grant a fixed amount of Experience, either 36 for Melee Heroes or 18 for Ranged Heroes. This Experience is still split among all Heroes in the area. Additionally, summoned units will only give half of their normal Experience when killed.

For more information on Experience, please see the main article here.

Buildings
Buildings are special units in the game, there are several types of buildings. They are immune to almost all spells, which makes them very strong earlier in the game.

Towers
Each faction has 11 towers, 3 on each lane that become stronger as they become closer to the base, and 2 guarding the ancient. Each tower is invulnerable until you destroy the one that’s before it, while the 2 towers located next to the Ancient must be destroyed in order to remove the invulnerability of the main structure. This means that the minimum amount of towers you have to destroy to win the game is 5. The middle or inner base towers that are attacked without nearby creeps will regenerate that damage at a rate of 90hp/second and take only a quarter of the damage from illusions. If there are creeps nearby they will not regenerate at all, and they will not regenerate damage from allied units either.

Barracks
There are two types of structures that affect the power of your faction’s creeps through the game, these are Barracks. That once destroyed will greatly improve most of the stats for the melee creeps of the opponent’s lane while reducing the experience and gold they grant when killed. That once destroyed will have the same effects as the above buildings but for ranged creeps and siege creeps only. Once you destroy all these buildings from your opponent’s base your creeps will instantly get all the upgrades at once, reaching level 30 and becoming almost unstoppable.