First conceptualized by Doctor Young as a means of strengthening the minds and bodies of weaker mental patients so as to allow for more extreme treatment methods, the doctor soon found herself financed by a mysterious investor named Jack White (an alias of the Joker). With his money, Doctor Young managed to ship the super-criminal Bane into Arkham Asylum, combining his Venom-lased blood with elements of Poison Ivy's plants. The combined chemicals created a Venom-like drug that would turn normal people into hulking, mindless monsters with only a small dose, similar to Bane's own drug. However, unlike its predecessor, it does not require a storage tank or excess amounts pumped into the blood stream to maintain the effects.
Its benefits do not come without risk, however. People using the Titan serum have their bodies morphed and distorted by the drug's effects, their skin and muscles splitting and enlarging, bones often protruding from their skin. The drug also lowers its user's intelligence significantly, to the point where they are little more than mindless beasts (Joker was able to resist this effect, possibly due to the fact that he was insane). These effects, along with the enhanced strength, seem to be temporary, as Joker (and possibly other thugs) reverted to his original form after some time. Titan users are often shown to succumb to heart attacks after some time, probably from the increased strain on their hearts while using the drug. The effects it had on Poison Ivy were different as she physically stayed the same (aside from green eyes) but it enhanced her chlorokinetic abilities.
The long-lasting effect of Titan is that, over time, the chemicals begin to degrade into poison inside the body, slowly killing the user. While infected, the person's skin loses color and begins to peel, hair begins to fall out, and a significant cough develops. If a cure is not administered after some time, the victim will die. Joker managed to spread this disease to the citizens of Gotham City by shipping his infected blood to hospitals for transfusion, with Batman being infected personally by the Joker in Arkham City.
Arkham AsylumDuring a patient interview with Joker, Doctor Young realized her mistake; Joker revealed himself as Jack White. Knowing he had planned to use the Titan formula for nefarious purposes, she hid her notes during the Joker's takeover of the Asylum. However, Joker still managed to apprehend what had already been made, using it on several of his henchmen, along with himself and Batman. By the game's end, a single crate of Titan is seen floating in Gotham Harbor before a hand (belonging to either Bane, Killer Croc, or Scarecrow) reaching out of the water and grabbing it.
A year later, Bane is attacked in Arkham City by one of Joker's Titan henchmen. He is nearly killed, saved at the last second by the henchman having a heart attack and dying. Realizing Titan is a threat to him, he enlists the help of Batman to capture the twelve canisters in Joker's control around the city. Each take half, with Batman destroying his six and Bane taking his back to his hideout. Upon discovering Batman had destroyed his canisters, Bane attempts to kill him, as he'd planned to use them for himself all along. Knowing this, Batman traps him in a makeshift cell before destroying the last six canisters.
Harley Quinn's Revenge
In the prequel story Batman: Arkham Origins, Bane possesses an experimental enhancement of Venom known as TN-1. After injecting himself with the drug near the game's climax, his more realistic and human appearance morphs into the musclebound form of the previous games. His intelligence seemed to decrease greatly. His long-term memory was also damaged, noted by his inability to remember Batman's identity, or even that he had encountered the Batman that night.
- The effects of Titan can be repressed by someone of significant willpower, shown when Batman is shot with a Titan dart by the Joker, but manages not to transform into a monster for a significant amount of time.
- Batman had managed to develop a cure for both the Titan drug and the virus that follows its usage (the latter with help from Mister Freeze). Both of these are used on himself.
- The Titan drug is similar in nature to the new version of Venom in the comics, created by Bane through combining his Venom with Scarecrow's Fear Toxin. 
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