Rickless, here's the TF bug:
The bug is this: Twisted Fate's Pick a Card does not properly convert sheen/lich bane/trinity force procs over to magic damage. I know, these procs are normally physical and yes, I know that most abilities that proc them don't change them over to magic damage. That said, Poppy's Devastating Blow and Morde's Mace of Spades both convert these procs to magic damage. I never thought TF's Pick a Card was supposed to do this, but WhattayaBrian made a post, about 2.5 months ago, that said that Poppy, Morde, and Twisted Fate's Pick a Card all converted damage over---that said, TF's PaC is not properly converting the procs to magic damage, currently.
Could you pass it on? It's so obscure and technical, no one seems to know about it.