In the words of Damien Darhk: "Well that happened." Obviously he wasn't referring to Conklin with that quote, but had he seen it it's probably what his reaction would've been because, well, yeah, it got weird. Was this actually Conklin's spirit that we were seeing here, coming back to haunt Baron Reiter, or are we dealing with some sort of Buffy-esque First type of villain, an evil spirit capable of manipulating those it interacts with? It let Oliver pass eventually, but is that the last we've seen of it?