When John Constantine appeared earlier in the season, the island flashbacks saw Hellblazer magically transfer one of his tattoos to the torso of Oliver Queen. Nothing has been mentioned on that front since until now. With Conklin whipping Ollie like a government mule (hey, JR!), things dont look good for our hero. All of that changes when Baron Reiter notices the magical, glowing tattoo shining on Olivers body. As a result, Reiter stops Conklin from doing too much damage, instead locking Ollie up in a cell. The sudden awakening of this tattoo was a WTF moment that was one of those happenings that piqued the interest about where this particular plot point will go in the future.