So Guardian is used to capitalize off of the new Shurelya's Battlesong passive Motivate, which gives Singed and an ally movespeed whenever he empowers or protects them.

Guardian procs this passive very easily, giving him and his ally a defense and peel. It is a very good teamfighting tool, since it both protects carries, and enables Singed to do Singed things (due to the extra movement speed).

Knight's Vow and Zeke's Convergence can be used to proc the passive, through protecting an ally or empowering an ally through flinging respectively.

Admittedly, Aftershock has a better laning phase, but Guardian seems to hold its own in teamfights.

Guardian in the laning phase plays like Predator, in the sense that they are both nonexistent keystones. But Guardian has the benefit of having way better runes, since Domination runes are garbage.

So far I've been playing this in smurf-queue normals games, while trying to level up my account (after getting banned), and its definitely a really fun rune. Don't know how well it would do in ranked though. You would probably just get dove because of the lack of keystone :\

tl;dr Experimental Guardian synergy with new Shurelya's, having a lot of fun with it in norms games, haven't tried it in ranked though. Made this guide to share the fun c: