Is Ezreal the Champion closest to being 'Main Protagonist' in League of Legends?
Even though because Runeterra is large with many different storylines which are not focused on a specific character, Ezreal is the closest one to the role of the main character. He is an adventurer with pretty appearance who explores the world and gains knowledge and power with his adventures. He has the ideal anime protagonist theme and characteristics that appeal to most of the audience. When someone is the main protagonist it does not mean that they have to be part in all the events, a lot of things can happen without them and sometimes others taking the central role but Ezreal is so far the most ideal character as a main protagonist in Runeterra.
http://img13.deviantart.net/4a1b/i/2014/313/4/f/ezreal_splash_base_rework_by_su_ke-d85w2uj.jpg
might fill that role more now with recent changes to Demacia's lore. She definitely has some wanderlust and not gonna lie she's much more interesting as a character than Ezreal. 
come closest to this, if we're taking things on a global scale.
- seems fairly obvious after Burning Tides imo; doesn't really need an explanation.
- people are probably wondering why he would be chosen over 
but I think it makes perfect sense when you realize that his bio gives him so much to work with. A general who travels across Rune Terra, interacting with & fighting off a variety of armies from multiple civilizations/cultures, started from nothing in his childhood and managed to work his (and his brother's) way to the top through sheer will, has a shaky, uncertain relationship with Swain and the rest of the Noxian elite; there's so much potential going for him.
- once again, he may seem like an unusual pick over someone like 
, especially when so many see him as a villain - but Riot did state that he's actually quite a gray character and that he is fighting to better Ionia in his own way; we'll see more of this in later lore updates. Plus he's much more popular and iconic than Shen and has more ties to other Ionian champions.
Too much of a given. Also helps that he has so many lore ties to both Zaunite and Piltovan champions alike.
Piltover - Really difficult to choose from, but I think it could go to any of the following: 
. Though lore is strongly leaning towards Vi, thanks to her connections to both Zaun and Piltover.
Shurima - If we take Taliyah out of the equation, then I would say 
for Modern Shurima and both 
& 
for ancient Shurima.
The Void - Before the recent lore updates, it was clearly 
, but thanks to new 
seems like the best candidate. Poppy, Kled, Rumble, Gnar, Ziggs and etc have stronger ties with other factions than Bandle itself.
Freljord - Tie between 
and 
. Or maybe even both.
Targon - 
. I don't think it's 
& 
because they're too distracted at warring with each other. Taric seems dedicated to his goals of stopping the Void.
Shadow Isles - 
seems like the initial given thanks to his lore and long-tern goals. The problem is, though - he isn't a very popular, appealing or relateable champ for most people. So this is why I see 
and overtaking the protagonist role. He seems to spend a lot of time over there since he's also obsessed with wiping out the Shadow Isles' curse. Now - ancient, pre-cursed Blessed Isles on the other hand - then it could definitely go to 
.
is probably the best choice.
as the main antagonist. 
is sort of the protagonist of his own side story, which is far less important to the setting overall but more deeply personal to the character.
comes closest with her shitty rebellion, along with 
as a particularly dark villain protagonist.
.
Or champs that are just nice people with no malicious motive, like 
, 
or 
.
Rom com anime?
