Do any of the in-game objects exist.
From the small amount of worldly lore we have (Worldly not characters) we have proof that both Twisted Treeline and Howling Abyss exist and that a few of the purchasable items are real
in particular. Baron is also confirmed to be a real creature and the in-game one was said to be a fake mimicry, however, the Institute lore that said that has been scrapped so I'm not sure anymore.
Sona still has a line about summoners, the map is still called Summoners Rift, and the spells are still called summoner spells, but there is no summoner lore anywhere aside from the Wikis which still contain the old lores.
How much of the Summoners Rift is canon to the official universe of League of Legends?
As far as I know,
is wearing it officially.
is the shoulder plate from
.
I think we can assume that it does exist and is hold by
.
(the sand soldiers)
Tool of the Iceborn, mentioned Lyte, the uncle of Ezreal
Worn by Gregor
All those items have lore in their description
In the old lore they had lore.
is used by... a Hero from Dota