Riddles In the Dark - An eye in a blue face saw an eye in a green face...

Riddles in the Dark - An Eye in a blue face saw an eye in a green face... (Found at 5th Ave/59th street station; downtown N, R & Q trains)

Riddles in the Dark - An Eye in a blue face saw an eye in a green face... (Found at 59th street/Columbus Circle station; downtown A, B, C  & D trains)

 Riddles in the Dark - An Eye in a blue face saw an eye in a green face... (Found at 28th street station; downtown 6 train)

 Riddles in the Dark - An Eye in a blue face saw an eye in a green face... (Found at Franklin Ave station; Manhattan bound 2 & 3 trains)

Riddles in the Dark - An Eye in a blue face saw an eye in a green face... (Found at 18th street station; uptown 1 train)

Riddles in the Dark - An Eye in a blue face saw an eye in a green face... (Found at Clinton Washington Ave station; Broadway Junction bound C train)

Riddles in the Dark - An Eye in a blue face saw an eye in a green face... (Found at Barclay Center/Atlantic Ave station; B & Q trains)

Riddles in the Dark - An Eye in a blue face saw an eye in a green face... (Found at Lafayette Ave station; Broadway Junction bound C train)

Riddles in the Dark - An Eye in a blue face saw an eye in a green face... (Found at Court street station; Manhattan bound 2 & 3 trains)

Riddles in the Dark - An Eye in a blue face saw an eye in a green face... (Found at 33rd street station; downtown 6 train)

Riddles in the Dark - An Eye in a blue face saw an eye in a green face... (2015)

Answer: Sun on the Daisies.