The Monarch Playing Card Company was the location where the Red Hood, trying to elude capture by the Batman after being involved in an attempt to steal money from the company, leapt off a catwalk and into a waste catch basin of chemicals. As a result, he was turned into the green-haired, white-skinned horror known as the Joker.
Now an abandoned factory, the Riddler has turned the building's lower floors into his own secret hideout; rigging the upper floors with tricks and puzzles to deter visitors.
Having been leaving clues for Batman to find; claiming that he knows who was behind Joker's latest chemical formula. Learning that Joker had hired Deathstroke to kill Riddler before he revealed his secret, Batman sends a new hero to the hideout to get to Riddler before Deathstroke does.
First Riddle Edit
What never speaks yet shows the way? Get to the point, it's clear as day!
The answer is "an arrow". Go to the far side of the room, directly opposite the entrance, then turn to your left. There is a faint white arrow painted on the floor in front of the delivery entrance (large steel garage door). Look at the arrow and a switch will appear on the wall a bit to the right of the delivery entrance.
Second Riddle Edit
Want to get past my LOCKS? Start to think outside the BOX! What I'm trying to CONVEY, will BELT you—so don't delay!
The answer is "the box near the conveyor belt". Interact with the box propped up against the end of the conveyor belt. The switch will appear on the wall behind the conveyor belt.
Third Riddle Edit
The answer to the final riddle? Me, of course! But you'll only get through if you solver all my riddles!
The answer is "the Riddler wanted poster". Do not go left to the Riddler hologram, go right and find the Riddler wanted poster on the other side of a pillar. Stand in front of it and the switch will appear on the same wall.
Fourth Riddle Edit
The middle son. the left path tread / With dreams of riches in his head.
The youngest took the middle pass; / A wife he hoped to find at last.
The eldest the right road did claim, / A fine estate was his good aim.
[...] Order not their paths, but instead their ages.
This is a simple logic puzzle. Pull the middle switch, then the left switch, then the right switch.
Monarch Playing Card Company DC Database