I can fill you in on a few details to Dota 2; I play it a lot to be 'OK' at the game. Not perfect, not pro but OK.
If you've already tried it, then these are some note's to take note of since they never tell you in the game straight off the bat.
Your Inhibitors in Dota 2 are Barracks; and they come in 2 forms. Melee Barracks and Ranged Barracks. If you destroy.... Let's say the Ranged Barracks for the top lane of your opponent, then the minions/creeps you spawn will get upgraded to SUPER Range minions/creeps for that lane. Destroy them both, you get both Melee and Ranged Super Creeps. Destroy All of the barrack's, and you spawn MEGA creeps... Which, if I had to describe them; you can think of them as mini-champions or mini-heroes with a high damage rate that can almost ensure your game has a slam-dunk... And UNLIKE League's Inhibitors, the barrack's don't come back; once they're gone, they stay gone until you start a new game.
98% Attack's and Spell casting are based on where your hero is facing... What does this mean? If you want to cast, say, Lina's Dragon Slave spell which is a ball of fire, she will turn towards that direction first before she cast's the spell. In fact, almost all of the characters will turn to face their targets when attacking or casting anything from debuffs to buffs and so on. The characters take less than a second to turn to face their target but in a life or death situation in a match, you'll find it a huge pain in the ass. The other 2% where spell casting's don't require the heroes to face are items, passives such as aura's and ultimate's or [R] skill's that affect everyone. - I know this was explained earlier, though a bright idea of detail is notable.
Wards help, they change wards and the rules about them every major patch update, but their purpose remains the same in their effect's. IF you get a yellow one, Observer ward, you can place them on Pillars with eye's plastered on the top of a decent ranged view of some areas or in the jungles to either HUNT a particular hero or DODGE a gank.
Next; READ THE PATCH NOTES! Not every single patch note out there, but when they perform a big one and announce it; read it thoroughly... Why? The patch notes include important game rule changes to the matches on EVERYTHING! The price change for healing Tango items, the removal and addendum or new hero spells/skills along with the new mechanic's. Which hero get's nerfed hard and which hero get's an unfair advantage in the next update... Do you have to read all of it? No; HOWEVER, it is important to read the general updates and the updates to new mechanics, know how they work. You can skim the rest unless your curious about your favorite hero or your most disliked hero... Why is this important though? The outpost's in the game's newest patch that give a rest teleport spot and true sight to the area can't be claimed until and after the 10-minute mark.... which is in the general updates and new mechanics.
There is a higher turn-around Rate in Dota 2 than LOL.... Or at least in my experience. I don't settle on one game, I dabble left and right; including Dota 2 and LOL. In League, once you lose your last tower, at the core, your attempt to make a comeback is sealed and there is no way to walk away with a win. Dota 2 on the other hand, you could loose your last tower, loose your barracks, just fiercely defended your base from an opponent's attack, stare down a massive wave of mega-creeps and still pull a victory from their cold, dead, taunting and toxic sludge-slinging hands.... And I've not only played but witnessed a large number of games where the players we're able to do just that... I know there are a lot of differences between Dota 2 and I'm willing to wager there are a few turn-arounds in League, though I have experienced this more and more going through Dota 2 than LOL. It's due to THAT factor why I still enjoy playing the game over LOL. If my opponent has a chance, I'd rather them take that chance and make the game hard, make it fun and worth playing. If I'm doing terrible, we're down to our ancient, I'll still stay in the game and fight until either ancient is dead. I would rather give the other team their worth in the game than to just lay over like some jack-ass and hand the whole game over to them on a platter.... I guess what I'm getting at is; it's one of the few reasons I love Dota 2 Over the LOL.... Just kinda wish there we're more players who would choose to play to the end than just give it up... If ya want; I'll post some of my matches on those or what was done to get through the end.
Which leads me to another feature not in Dota2; you can't forfeit mid-late game. Dota 2 Tournament's have that option, since they're on a time crunch to start, but all standard matches do not have that option. A lot of people abandon the game mid-way just by simply leaving it; which is doable, though if you do it too many times for being a sore sportsman, they can put you on a 6-month ban; continued ban on that caliber can earn a permanent ban through IP and steam account... Just don't Leave your games mid-way unless it's safe.
In LOL, you have you 3 Damage Types: Ability/Magic, Physical, True Damage.
Dota 2 has: Magic, Physical and Pure.
There is a Difference between the two on True Damage and Pure. True damage can be blocked by HP shields and other effect's. Pure Damage in Dota 2 IGNORES all armor types from Magic to Physical and deals the damage directly. I've yet to see a Re-work on the types since then.
Last bit and I'll hush; Though I don't know what governs the stats in LOL; The stats in Dota 2 champs are determined by 3 Attributes.
Strength: Determines your Max HP, how much health you regenerate and your resistance to magic Damage.
Agility: Determines Move Speed, Attack Speed and Armor... Which deals in Dodging attack's and litteral armor... I don't know why, but it's the games mechanic's, Blame Ice Frog and Blizzard, I didn't write the rules.
Intelligence: Determines Mana Pool, Mana Regeneration and your Spell's Amp..... The last being how much more damage does your spell do. It's a small but noticeable number.
There are items that cater to these traits and the secondary stats, So be sure about what you need while in play.
.... I think I went overboard on the primer... I hope it helps.
