Lizzord
True name: Tom Harrigan (altered; original one unknown)
Classification: Animorph
Occupation: Genetic scientist
Personality: There are basically two independent personalities, capable of thinking reasonably and even confront (or simply conversate) each other.
The first one, is the personality of Tom Harrigan. A reserved scientist, shy and locked up in himself, misunderstood by surrounding people. Quiet and not outgoing, he feels best when he is alone, not disturbed by the others.
The second one, is the personality of Lizzord, a vile Lizardman that was accidentally created by Harrigan. Although highly intelligent, Lizzord is a cruel beast, with lust for blood, who get pure joy and satisfaction from killing and bloodshed (as well as eating the flesh of his victims). A psycho with sense of humour - very black one. He is also very proud, confident in his abilities, and sees all other creatures as inferior.
History: Tom Harrigan was born in Los Angeles, in a poor family. He graduated the studies of biology and genetics, and took a job in a large pharmaceutical company. He was a husband and father to two children.
In addition to his usual work for the company, Harrigan also led the research on his own, basing on the animal DNA. During his work, he created - among the others - a serum based on lizard's genetic code. One day, during an accident in his lab, the was cut by the broken test-tube, containing that serum, which got into his blood. During first week after this, there were no symptoms of the infection, so Harrigan believed nothing happened. Yet in the second week he became terribly ill, which forced him to stay at home for that time. In the last day of that week, he transmutated for the first time, turning into human-shaped, lizard-like monster, the Lizzord. This, however, happened when he was alone at home, and he kept this fact in secret (he also believed, at first, that it was only a dream, because he lost his consciousness then, and later woke up in his bed in fine condition. Yet he soon realized, that a new "person" was born inside him. A "person" that quickly began to develop his own consciousness, and planned on taking full control over Harrigan's body and mind.
This eventually happened one tragic day, when Harrigan, driven into state of madness by Lizzord, killed his wife along with children. After realising, what he has done, he fell into despair, and his mind became easy target for Lizzord, who took full control of him, transmutating his body into reptile form. He then left Harrigan's home.
The time when Harrigan was fully controlled by Lizzord, lasted for two years. The Lizzord learned about his life and the humanity, killing people regularly to indulge his lust for flesh (he even defeated two superheroes - Deathwing and Drake - that tried to stop him). Day by day, it was becoming more and more hard for him to keep Harrigan at bay. Tom finally regained his own consciousness during Lizzord's attack on a family with two children, which reminded Harrigan the death of his own wife and kids. Barely controlling the Lizzord, he set on a journey in an attempt to begin a new live. Assuming new name, by which he is now known, he finally got to New York, taking job there, and eventually beginning his new career in Deckard's company. He was quite quickly promoted there, due to his skills, and became the leader of genetic research division, as well as good friend of Deckard himself.
At the time, when Kagar reemerged, Lizzord came to voice again, beginning to temporarily control Harrigan and transforming into reptile. It was then, when he tried to gather the crystals of elements himself, but he eventually joined sides with Deckard, forging an alliance with him. At this time, also Harrigan and Lizzord were beginning to form a peace between themselves. Tom, knowing that Lizzord won't keep his bloodlust at bay for too long without an ability to kill someone, made a simple deal with the reptile, proposing him to find vent to his lust for killing by slaughtering the bad people instead of good ones. Namely, criminals.
Lizzord soon left New York (taking an arsenal of gadgets, that were designed by Deckard especially for him, to enhance his combat abilities) and moved to Chicago in order to fight the local mafia, and thus find an occupation for Lizzord, who was eager to kill (killing proved to be like a narcotic for him - it brought him joy and satisfaction). He even forged an alliance with local police officer, who served him as an informant. Lizzord successfully massacred whole mafia, including two humans - man and a woman - possessed by the Fallen Ones (named Diana and Gabriel). It remained unknown, why did the Fallen Ones decided to became a leaders of mafia.
After returning to New York, Lizzord joined the team of Deckard and CyClone, but was rather not a permanent member. After helping them by defeating rogue psionic James Anderson, he left again, moving to San Francisco and fighting local mafia (and finding another ally in the police again). The criminals, however, proved to be more dangerous enemies to the Lizzord, as they used reptile's blood, left by him at one of the places he appeared (and was shot), to create a biocyborg, made as Lizzord' evil twin. This cyborg was known as Blackclaw, and engaged Lizzord in few battles - for the first time while assisting the criminals in robbing the bank, but he left before the fight was finished. The second clash between Lizzord and Blackclaw took place in warehouses, and almost resulted in cyborg killing the reptile. Lizzord survived, however, and used weapons made for him by Deckard in the next battle, which occured in one of mafia's hideouts, at the time when Blackclaw started to rebel against his makers, killing all people in the hideout. Lizzord took the upper hand in the third fight, but was unable to destroy the Blackclaw, who eventually escaped. Most of Lizzords equipment was damaged or exhausted during the third fight, so he wasn't able to use it again to his advantage. But Harrigan intervened, creating a serum, that temporarily increased Lizzord's powers and aggresiveness (thus risking the loss of control over the beast). This gave Lizzord the advantage in the last clash with Blackclaw - reptile successfully defeated his, dismembered, and then threw parts of his body into acid, drowning it wholly.
After his victory, Lizzord returned to New York to aid Deckard in battle against Kagar again. Then he again left the team of heroes, to move to the Chicago again, when a new psionic, known as The Tamer, emerged. That psionic caused the transmutation of five people into animorphs (Lion, Tiger, Werewolf, Minotaur and Gorilla) and then took psychic control over them, when their animal sides were still not developed, as was their control over them. Lizzord found an ally in person of female police officer Crockett, who initially tried to find and arrest him (Lizzord saw her only as ally, but Harrigan fell into love with her). Because of the enemy advantage in numbers, Lizzord was unable to overcome Tamer with traditional methods. He drove the animorphs away from their master, and then attacked him directly. Then he discovered, that Tiger and Werewolf were still protecting Tamer, which led to a fight, that Lizzord hardly won (not without discovering, that Crockett was kidnapped by his enemies for blackmailing him - as it didn't stop the Lizzord from attacking, hostage was killed, and Harrigan mourned her). Infected with Werewolf's saliva, Lizzord was also forced to repel the Tamer's psychic attacks, who tried to control him. The psionic did not succed, however, and was killed.
Later Lizzord rejoined and left Deckard's team various times, e.g. fighting Minotaur (and later Werewolf), who gained control over his human self and proved to be powerful enemy for Lizzord (his abilities were earlier limited by Tamer's influence) due to his superior physical strength.
POWERS AND ABILITIES
Strenth level: superhuman, capable of lifting 10 tons
Martial arts skills: archmaster, unbeatable close combat fighter, employing his own sophisticated fighting style.
Special abilities: superhuman strength and unmatched reflexes (capable even of dodging bullets). Instant regeneration skills, healing wounds in matter of seconds (making him impossible to kill by most weapons). Capable of spitting acid (like a snake, spitting with poison) from glands in his mouth, at short distance.
He can also arm himself with an arsenal of weapons and gadgets given to him by Deckard (including two wristblades, lance, harpoon thrower, breast plate for protection, explosive charges, and synthetic, organic "fuel", perfectly sustaining his regenerative abilities).
Resistances: regeneration mentioned above. Limited invulnerability. Immunity to psychic attacks of any sort or mind control (due to the existence of two developed personalities - one takes the attack, the other functions normally).
Weaknesses: uneffective in combat at distance. His regeneration is limited and relies on the food he has consumed (flesh is the best "fuel"

. When angried, he may enter frenzy, losing control of himself and making him dangerous even for allies.