Syndra and Varus are confirmed not to be tragic villains. Syndra's a grown Annie with inmense magical powers that she wants to test out around. For that, you cant really call her "evil", even tho she just killed the master that tried to seal her magic. Neither is Varus a bad guy, since he sacrificed his belief and obtained dark powers to fight back the noxians.
Zed, however, believes on a darker path and thinks on eliminating people that opposes him. While the path of light and dark can be justified, Zed's way of doing things are not "right". So we can claim he's the very first 'villanous' Ionian champion.
|Free to delve further into her art, Syndra now aims to grow powerful enough to destroy the weak, foolish leaders of Ionia - and anyone else who would dare to shackle her greatness.|
Sure, Zed may have the darkest intentions of the three (four if you count Yi), but only by a little. All of them wish for more death for their own personal reasons. I'd say that's rather villainous.