Campaign mode/Story Mode
League of Legends seems to have lots of lore but it seems rather incomplete. I suggest Riot Games takes ideas from Blizzard Entertainment from games such as Starcraft II, Warcraft III and Diablo III.
This mode can have multi-player or single-player PVE gameplay.
Please look up the link I have provided. Gaming Curios can make things clear of the point I am trying to get across. What are your agreements or disagreements?