|“||My name is Alex Mercer. I'm the reason for all this. They call me a killer, a monster, a terrorist... I'm all of these things.||„|
|~ Alex Mercer|
Alex Mercer is the playable character of video game, Prototype.
As a human
Once a human, Alex works for a company known as Gentek. He has no empathy, as evidenced when he is questioned of how does he feel of creating a deadly virus to be 10x deadlier, he replies that he "wasn't paid to feel".
One day, he is pursued by Blackwatch, a military unit and took a vial of the virus as "insurance". Alex is cornered by the team in Penn Station. As a result, he drops the vial to the ground, hoping to release the virus and put Blackwatch and Gentek in a untenable situation. He is shot to death afterwards.
As a virus
His body is shown being brought to Gentek for dissection. the virus, having merged with his body, became an independent being based on Alex, codenamed Zeus. Zeus woke up, having no memory of how did he end up there, and tries to escape. Just then, Blackwatch corners him and shot him, but he survives.
Alex gets into contact with his younger sister, Dana Mercer, into helping him discover the truth. She even directed him to Karen Parker, his ex-girlfriend, to create a cure for the virus. However, the latter is possibly forced to work for Blackwatch as the genetic material he got for her is used to make a weapon against him. This is removed from him with help from Dr. Bradley Ragland.
Just then, Dana gets kidnapped by a Leader Hunter under orders of Elizabeth Greene. Alex has managed to locate her, and gets into a fight, but ended up creating the Supreme Hunter when he injected her with the same weapon. He saves Dana, nevertheless.
Next, Alex gets into contact with a mysterious informer, who knows everything about him. He reveals that he is the virus, and that Alex is just his role.
The contact lead him into a confrontation with Director Raymond McMullen, his ex-boss at Gentek, to get information. The latter reveals of how Alex Mercer is responsible for the plague by unleashing the virus in New York before having died at Penn Station.
Alex finally meets the contact, Captain Robert Cross, the specialist he fought early on. He reveals information on getting Colonel Taggert as a ticket to get into the Reagan to stop General Peter Randall from destroying Manhattan with a nuclear missile. When they got there, Alex absorbs Randall, and gets attacked by Cross, who is revealed to be the Supreme Hunter in disguise.
Alex defeats the monster, and puts the missile into the river. He fails to escape as the explosion takes him, too. However, his remains absorbed a crow, regenerating himself.
Prototype 2Alex has witnessed a soldier named James Heller taking down the infected. What he didn't know is that he does that only to die fighting them.
When Heller becomes wounded, Alex infected him with the Blacklight Virus, giving him the powers he would have. This leads him to have a vendetta for Alex as he knows he is responsible for the death of his wife and daughter.
The original Alex was a cold monster with no empathy who ultimately unleashed the virus out of pure spite. His actions and demeanor is likely due to his troubled past, which made him cold individual, both paranoid and sociopathic. On the top of that, he seemingly doesn't care about his younger sister, Dana, and is seemingly only using her as a pawn in his plans as well. He rarely takes human cost into account during his actions, being able to murder scores of humans without remorse or hesitation.
But in truth however, Alex is not completely heartless as he seemed; actually, he deeply trusts and cares for his younger sister Dana, having been the only real paternal figure for her, and had what can be assumed to be a loving relationship with Karen Parker.
The virus creation that merged with him, Zeus, was ultimately a better creature, displaying acts of genuine heroism and was horrified and disgusted with the original's actions. Even he is seemingly more caring to Dana after infected by Blacklight virus, as she is the only one who can help him to uncover his past. However, his change is likely because in truth, he is already dead when infected; His lifeless body was resurrected, taken over, and possessed by virus that he unleashed and immediately took control his mind, something which explain his amnesia upon his return. In addition, before being merged into Zeus during his death, Alex was a contrast of what he become now. He was positive, and full of life and often played games with his sister Dana despite his troubled past, showing a close bond between the two. However, when Dana betrays Alex at the end of the game, she says "the Alex I knew died a long time ago" Alex was hurt, but then said "I'm beyond life and death".
Unfortunately, after repeated betrayals and mishaps during his time away from NYZ after the initial outbreak, Alex decided that stopping the outbreak was a mistake and started a new one himself to usher in a new race; he claimed he was making a better world by doing so. In his new role as the leader of the Infected, Alex pursued his goal of spreading the virus in a far more active and aggressive manner than Elizabeth Greene ever did, even inserting spies within both Blackwatch and Gentek and using their resources and scientists to do so.
☀Once reanimated by the Blacklight virus, every particle of Mercer's form, including his clothing and equipment, becomes comprised entirely of viral biomass. This substance can be manipulated at will. He can absorb the organic matter of other living creatures, converting it into more biomass. This process sustains and regenerates Mercer's health and is referred to as 'consuming'. In addition, Mercer can consume individuals, absorbing their knowledge, skills, and even their physical form, which he can call upon at will. He can manipulate his physical form to create weapons to attack his enemies, generate armor to defend himself, and take on the appearance of another person to disguise himself.
Shapeshifting: Mercer's Blacklight infection has granted him the ability to both shapeshift and fashion his body into weapons. An example this would be his Blade resembling a giant sharp blade and his viral flesh possessing a yellow/reddish hue. His Whipfist has small razor-like blades across its spine-like form. Alex's evolved Hammerfists allow him to perform area attacks. He possesses consumption/assimilation abilities inherent in all infected creatures that allow him to take on the form and memories of any creature he consumes.
Superhuman Strength: His incredible strength allows him to lift cars, trucks, the destroyed remains of tanks, APCs, and helicopters and throw them great distances. He is far stronger than any normal human or most basic Infected, able to kill a regular human with a single, glancing blow and manhandle the infectious residents of Manhattan. Mercer is capable of punching holes through almost anything if necessary, including a two-foot steel door.
Superhuman Speed: Mercer's speed is likewise enhanced. He can achieve running speeds surpassing any vehicles including Helicopters.
Superhuman Agility: He can perform amazing parkour feats such as flips and rolls and maneuvers over and around vehicles and debris with little trouble. His leg strength allows him to leap nearly ten stories into the air. Mercer can run up sheer vertical surfaces and cling to walls for an indefinite period of time. Mercer is also capable of gliding, by ejecting small amounts of mass for further propulsion.
Superhuman Endurance: Mercer's endurance far exceeds that of a human's by leaps and bounds. His body no longer possesses weak bones or vital organs, rendering him immune to otherwise debilitating injury. This biological change allows him to survive falls from any height completely unharmed. Bullets of any caliber will pass through his body, causing very little damage that heals instantly. He can withstand direct hits from rockets, hellfire missiles and tank shells, which cause only moderate damage. The superhumanly strong blows of the various type of Hunters and super soldiers cause the most damage of any type of attack. His superhuman stamina allows him to be physically active at all times without tire.
Healing Factor: Mercer's body has vast powers of self-regeneration. So long as he is properly nourished, Mercer can restore his health and heal any wounds within moments. He can heal a small amount of his health even without consuming any creature. Examples include regenerating bullet wounds instantly after being shot, regenerating a massive hole in his face after being shot point-blank by General Randall, and reconstructing his entire physical form from non-descript piles of biomass and the biomass of a crow within minutes of being blown apart by a nuclear explosion. Mercer also seems to have a robust immune system. Though unable to counter a parasite which had been introduced into his body without outside help, he gained a growing immunity to bloodtox with repeat exposure.
Superhuman Senses: Mercer's vision and hearing is enhanced, allowing him to see beyond the visible spectrum and hear across great distances even with physical insulation. He has thermal vision which allows him to locate heat signatures, and infected vision which can detect large concentrations of the virus and tap into the hive mind itself.
Durability: Mercer's body is greatly increased that he can survived extreme blunt trauma, he can survive through collapsing buildings fall on him and walk out of the rubble as it was nothing. Mercer can take shot from a rocket launcher and can only be push back a bit by the force without blowing to pieces like a normal human.