Tahm Kench, Minion Vomit, and Windwall
Okay I officially don't know what a projectile is anymore. I just watched (spectating a firends game) Tahm Kench spit a minion through windwall. By all definitions of projectile that I can think of that should not have happened. I mean even Oriana's ball is stopped by windwall, and that is less of a projectile than the minions Tahm Kench spit are.