Villians in Runeterra

Any other champ could be seen as a "hero" from their point of view.

When Hecarim and Thresh were still mortal men, they had nightmares about the legendary necromantic warlord known as Mordekaiser.

She has been systematically murdering and replacing her own biological children for several hundred years now. That is pretty twisted.

She's smaller scope than other villains, but she still is motivated entirely by selfishness and has no redeeming features.

I love his new lore, because it makes him understandable without making him any less villainous. It feels good to be bad.

She killed Frey. Enough said.

It's hard to apply morality to the spirit world, but this guy only exists to spread misery and despair.

Destruction of the entire universe? The fact that he is actually human is what makes him "villain" instead of "monster".

Pretty much any of the Void champs, darkin, or demons, as well as the Shadow Isles champs sans Yorick, Kalista, and Maokai. Jhin and Lissandra, as well.

From the Void: well everybody

Shadow Isles: Everyone except for Yorick, Mao'Kai, maybe Kallista

Demacia: No outright villains as of yet.

Noxus: Swain definitely, LeBlanc, Sion, Vladimir, Elise, The argument could be made that Katarina, Cassiopeia, and Talon are also de facto villains

Piltover: Camille

Zaun: Viktor has villainous potential, Urgot, Warwick also has potential, Singed, Mundo

Ionia: Jhin, Zed, Syndra, Kayn, maybe Xayah

Freljord: Brand, Lissandra, Volibear, Maybe Sejuani, by extension Olaf also

Shurima: Xerath, Renekton

Targon: Maybe Aurelion Sol

All the demons: Shaco, Nocturne, Tahm, Evelynn

I may have missed a few, but I think that sums it up

Edit: Aatrox, Fiddlesticks, Veigar, Gangplank, Graves, Twisted Fate

I want to add also and

Basically, Cassiopeia is a sadistic temptress, Jinx wants to destroy things and loves Chaos, Morgana is kind of an evil witch, Vayne is now a shadow huntress, but she has no more empathy and likes to make suffer and Zyra is a predator who feeds on her prays.

was designed to be a supervillain.

Most void monsters only want to consume/destroy stuff.