That suggests that at least for now, the plan is for trading to only be available for older sets, presumably the ones where hardcore players have already maxed out most of their library and are just chasing a final handful of cards that still havent come up in packs for them
Its a solid and reliable effect, with the bonus of being a spirit fitting into some kindred archetypes
Sanctuary Warden provides excellent value in a blink deck, drawing cards from its shield counters or other counters you want to remove (like the flying counters from Luminous Broodmoths effect)
Put that card onto the battlefield tapped and the rest on the bottom of your library in a random order
And yes, for those who are unsure, that is Liliana in the art getting her "contract" (the full-body tattoos)
All you have to do is have both of them in play, and then attack with both of them