Batman and Veronica continued on, following the green trail to the next room. This one appeared to be a study with a writing table and high-back leather chair. A modest bookshelf stood along the wall, its volumes blanketed in dust. The lights in the floor moved along directly to the door on the opposite wall. The next room would be the library, Batman recalled from the blueprints.
"Batman, how are you figuring this stuff out?" Veronica asked. "These games are impossible."
"Every riddle has a clue inside of it. Examine the clue and find the pattern. The answer to unlocking your tank was the periodic symbol for oxygen. Penguin's was the symbol for sodium chloride."
Veronica made a face. Science was never her best subject in school.
Batman opened the next door. He was right, this room was the library. It was the largest room in the entire house. The ceiling rose to the third of the mansion's four stories. There was a stairwell to the side that led to the next two levels. Slide ladders stood at the corners for the higher placed books. Even he was taken aback by the amount of books crammed into the shelves that covered every wall. The only areas that didn't have books were the few 4x30 foot stain glass windows. Charles Darwin's research would certainly never go without resources.
More power cables snaked along the floor and up corners and around the balconies of the next level. The Riddler's green mood lighting was somewhat lost in the vastness of the massive room.
The illuminating trail took them around a bend in the wing and stopped in front of a tall curtain covering the east corner. It had question marks painted on it. A loud thump sound cracked through the air. Batman felt Veronica flinch behind him. The curtain dropped revealing a small stage with another tank sitting in the center of it. Green spot lights flicked to life and featured the prisoner inside, sitting and leaning against the glass: Nora Fries.
Four mirrors were placed at the top of the tank, each one positioned to reflect rotating green lit symbols created by a specific combination of the spotlights. Above each mirror was a red button being powered by its own arc of electricity.
"The brilliant Doctor Nora Fries," the Riddler said. "The daughter of one mister Rupert Thorne."
"What?" Veronica whispered to herself.
"Crime truly is in this ice queen's blood. Let's see how fast she melts!"
Inside the tank a flame sparked into existence. Slowly it grew to comsure the entire top of the tank, similar to Veronica's tank after Riddler decided that Batman had cheated. It grew larger still and flames began to spit downward closer to Nora. The doctor's eyelids hung as if she had just woken up from a deep sleep. Her skin was pale and her lips were cracked and dry. She weazed and hacked a deep cough.
Batman watched the rotating reflections of the symbols. Similar to the previous puzzles he had to stop the correct symbol just in time so that its reflection is left in the mirror.
"Fire!" Veronica said. "You said the puzzles were based on elements like on the periodic table. Fire is an element. Like air and water. What's the periodic symbol for fire? Oh my god I can't believe I just figured it out!"
"Fire is not a periodic element," Batman said.
"Oh."
"Ice Queen. In her blood," Batman said to himself. He was repeating the Riddler's words in his head and corresponding them with the rotating symbols in the mirrors.
The fire inside the tank sank further. Nora was starting to stir. She moved weakly like she was struggling against an invisible force attacking her.
"Fire is not an element," Batman said. "It's a plasma. Blood is plasma. Made of proteins. Carbon, hydrogen, oxygen, nitrogen."
C, H, O, N, Batman thought. That's the right combination. Each of those letters were represented in the rotation on a different mirror. He drew a Batarang and reared it back, but suddenly stopped himself from throwing it. The red button above each mirror had a different colored cable running from it. He traced a green cable with his eyes to a light projector that was reflecting an H letter in its rotation on a different mirror. The red button above each mirror was not connected to the projector facing it. If he struck the wrong button at the wrong time it would surely mean a fiery death for Nora.
Inside the tank, Nora passed out. The flames were just starting to lick her flesh.
Veronica gasped and turned away.
Batman was out of time. He traced the different cables to their appropriate light projectors. In quick succession he let loose four Batarangs at the red buttons. After the last one hit, a cheery bell sounded resoundingly as if Batman had just won a prize on a game show. The flames inside the tank evaporated. Slowly, the glass tube shifted and sank down into the floor.
Batman rushed to Nora. She was barely conscious now, but breathing. There were no serious burns and most of her hair was singed.
"How in the–" Riddler said. He stopped himself mid sentence. He was trying to keep his cool. "Well…Batman, you've–"
Riddler's voice cut out of the PA. This time, not only did the house's audio system fail, but the lights flickered.
"Batman," Robin said in Batman's ear. "It's done. The servers are dead."