|“||No need. Dracula doesn't have her. I do. She's in my pen.||„|
|~ Codex revealing his true colors to Lex.|
|“||I never could have done it without you. Letter by letter, word by word, you broke the chains of fiction that held the beasts within their books. And now they are mine to control!||„|
|~ Codex revealing his true plans to Lex during their showdown.|
Professor Codex was the main antagonist of the PopCap video game, Bookworm Adventures. He appears after the events of the online version of Bookworm Adventures. Professor Codex is an anthropomorphic stork who uses the Magic Pen and initially helped Lex the Bookworm in the first two books. However, after he revealed his true nature in the third and final book, he became the final boss of the game.
Pests in the Great Library
Professor Codex orders Lex to get rid of all the literature characters causing havoc in the library. After Lex faced his final enemy Odin, Codex possibly thanked him for doing so.
Wanting world domination, Codex planned to use the Magic Pen to summons monsters from the books to achieve this. Fearing that Cassandra the Oracle would be a threat, Codex used the pen to seal her inside the first book, which was about Ancient Greece. When Cassandra called out for help via a message in the book, Codex called Lex and showed him. He convinces Lex that Cassandra needs help, because she is captured by Medusa. He uses his Magic Pen to send him into the book.
After Lex defeats Medusa, Cassandra attempts to warn him about Codex's true nature. However, Codex arrived, disguised in a red cloak, and silenced Cassandra by snatching her away. He then quickly sealed her inside his Magic Pen. As Lex returned, he tells him the the true villain "drains essence", Codex instantly said it was Dracula that was the mastermind, only so that he wanted Lex to further disrupt the books so he can summon his army. He then sent him into another title "Arabian Nights".
After Lex returns with the Scimitar of Justice, he sees Codex being transported to Dracula's Castle. He is able to follow him before the book closes. However, little did Lex know was that Codex did that to ensure that he would believe his theory
After Lex defeats Dracula, he finds Codex wearing a familiar cloak. As they return to the Great Library, Codex reveals that he kidnapped Cassandra and was manipulating the entire time. He further explains that since he travelled through the three books and defeats their monsters, he would have better control over them. This way, he could build an entire army of literary characters to take over the world. Lex is able to defeat Codex and his summoned monsters.
Losing what's left of his sanity, Codex attempted to destroy him, keep Cassandra trapped and summon an even greater army of villains to unleash and heroes to enslave by using every literary book in the Great Library. However, just before he was able to do so, Lex used the word "Hippopotomonstrosequipedalian" to overpower him and trap him inside the Magic Pen, therefore defeating him once and for all.
After Codex's defeat, the monsters he enslaved were freed and returned to their books. Cassandra then made Lex the new Guardian of the Great Library following Codex's betrayal.
At the end of Bookworm Adventures, Vol. 2, the Magic Pen was exhausted due to being used by a machine as a fuel for power. Therefore, it would have to hibernate itself so it can heal. It is unknown what became of Codex due to still being sealed inside the pen.
Professor Codex is the final boss in the game. The beasts he will summon are Cerberus, Medusa, Shaitan, and Wolf-Man. All four have ten hearts, but are still just as powerful as they were before. Codex, however, is deadlier to defeat because the player must have enough potions. He is immune to three to four letter words. His first move depends on how the player defeats his minions: if the player knocks them all out quickly with large words, he will use his Pen Blast first; but if the player defeat his minions more slowly, he might use Book Slap instead.
|Book Barrage||[Bld][Att]||Cuts and damages Lex.||Three books fly to Codex, then he throws them at Lex.|
|Book Slap||[Smh][Lck][Plg]||Smashes tiles, locks tiles, and plagues a tile.||An open book appears in front of Lex's face, then Codex closes the book on Lex's face.|
|Power Surge||[Hal][Prf][PoU][PoD]||Heals and purifies enemy, boosts enemy's attack, and weakens Lex.||Codex hangs the Magic Pen high up, then a flash of lightning strikes to him.|
|Pen Blast||[Psn][Brn][Frz]||Poisons, burns, and freezes Lex.||Codex throws the Magic Pen to Lex, then appears at his hand after it hits Lex.|
|3+4 Letter Immunity||[Imm]||Enemy is immune to 3 and 4 letter words||3 and 4 lettered words cannot be used to attack him.|
- Before his true role in the game was revealed, the color of Codex's avatar was blue, which showed that he was one of the protagonists; and when he was revealed to be evil, it turned red which matched the color of his cloak.