From a high enough altitude, Dota 2 isn't unique. The original Defense of the Ancients spawned numerous proper repackagings and reimaginings, from League of Legends to, more recently, Heroes of the Storm. In each of these games, as you level up, you can gain new abilities or make existing ones more powerful, and it's these abilities that generally determine what role you should play in your team. But it's in the particulars of its execution that Dota 2 stands out.
Although the community has always maintained certain customs about the best way to play, Dota itself has never enforced a particular methodology. This is the key thing that separates it from its peers, while other MOBAs have tended to fold the community metagame into the design of the games themselves, codifying player roles like tanks, supports and damage dealers as fixed archetypes within their rosters, this doesn’t work quite the same way in Dota 2.
On the flipside, it's crucial to keep your team Creeps in front of you to soak up incoming damage, as towers attack Creeps before turning their attentions to Heroes. That said, if you hit an enemy Hero in the range of a tower, the tower will attack you even if Creeps are present. This creates an array of interesting strategies. A basic strategy is to force the enemy to leave a lane, but damaging them just enough so that the team is scared to engage in combat. Then, help your Creeps advance the lane until they get in range to attack the tower.
Everything changes in the next match, as 10 players pick 10 different heroes out of the roster of over 100. Friendships form as a strong showing earns you an invite to a recruiting clan. Meta strategies evolve as heroes and team compositions fall in and out of favor from week to week. A popular professional player throws a tournament pool into disarray by choosing an unconventional item progression, and everyone from mid-tier rankings on up scrambles to adjust. You can get Dota 2 MMR Boost Cheap services from boostingvip.com.
Aiding these two teams, named the Radiant and the Dire, are waves of AI assistants, called creeps. Batches of creeps spawn at 30-second intervals and charge merrily up the map's three pathways. In the clumps of remaining land lies a jungle, where numerous AI opponents spawn, offering lucrative benefits to players who take them on successfully. Finally, and in a bid to stop both teams from simply marching into one another base, each team gets three powerful towers on each lane that easily shred through enemy players at the start of the game.
Developing a familiarity with all of these different components might take 200 hours. To know how to combine them instinctively, you are looking at 400 hours. Which isn't quite the mortifying challenge it sounds like. Yes, by the end of your first six months of Dota 2 you'll have skimmed an amount of knowledge from the surface of the game comparable to six months at university, but you'll have had fun doing it.