row 1, Riddle 1
Gotham Casino - On the east side of the building, you willl see three pieces of building sticking out. You want to look at the north side of the southern most piece which will have a giant poster for "The Flying Graysons" CANCELLED.
row 1, riddle 2
Just south of the GCPD is the Krank Co. Toys building. You want to scan the giant sign and bear.
row 2, riddle 1
SE of the Gotham Casino, you will see the Gotham City Olympus. Above the sign is a statue with a blue lightning bolt in it's hand. You want to scan the blue bolt. If you have trouble, you can scan it while gliding to get closer.
row 3, riddle 1
If you stand on the Gotham Casino and look south, you will see three water towers. Under the right most water tower, you will see a motor (still on the roof) above what looks like a door but with no shutter. You need to CLOSE the shutter. On this shutter is the dot for the question mark. If you look directly North of this spot, you'll see a building with a billboard. Stand just on the other side of the billboard on the small raised section of roof. On the back of the billboard is the top of the mark. Turn on detective mode and then line up the part on the billboard with the dot on the shutter in the distance.
row 3, riddle 2
GCPD Vehicle Access - After collecting the second statue from here, line launch across the water to where Catwoman's statue is/was. After landing, turn left and you should see a couple of parking spots. Scan James Gordon's spot.
row 4, riddle 1
Stand on top of the GCPD and look ENE. In the distance, you should see an island. Zoom in to see that it is Arkham Asylum with giant plant overgrowth and all. Scan this.
row 4, riddle 2
GCPD roof - On the north side of the roof will be the Bat Signal. Scan it.
row 5, riddle 1
Go to Poison Ivy's building NW of the GCPD. It is made up of two buildings connected by a catwalk. If you look in the water between them, you should see what may, at a distance, look like a bed floating in the water. It's actually a containment cell. Scan this.
row 5, riddle 2
On the very top of the bridge leading to the Industrial District, you will find a pile of hay and mask. Scan this.