Thanks for all the answers everyone! I'm gonna ask some more stuff though

Are there invisible heroes at all? If so can you counter them?
I understand there are skills that every hero can have? Such as a blink and tp? If so how is it balanced,is there a mana cost ? What's the cool downs like? Can you teleport to towers?
Is there something like smoke in the game?
Also, I assume there are people here that have made a transition from one of the games to the other, I wonder, what's been most difficult to get used too?