My favorite use is to make an instant creature with an enters-the-battlefield (ETB) trigger
Dont attack into their Archangel Avacyn with your Angel of Sanctions unless you have the kill spell, just like you wouldnt attack with other creatures in the same spot
The most obvious one is with Beseech the Mirror, but I am sure there are others out there
By the second night after the kami had drifted into town, the local general store was completely sold out of earplugs
A tapped black source is kinda eh, and Wraith typing is narrow, BUT Granting a creature shadow is very strong
Well, not exactly, but I find it funny that some of these proxies from Elkoytcg on Etsy, like the Mew one (The First Sliver), are on-point references between Pokmon and what the MTG card actually does