Lucas Baker

Lucas Baker was a resident at the so-called "Dulvey Haunted House", a mansion in the Southern United States. He was the son of Jack and Marguerite Baker, and the older brother of Zoe Baker.

Pre-infection
According to Andre Stickland, Lucas was allegedly a "bad seed". Despite his unruly ways, he was a gifted inventor and won several awards for his work, as can be seen in his room. As hinted in Lucas' journal, it can be presumed that he was mentally unstable. He also chronicled the time when he trapped one of his childhood bullies, Oliver, in the attic and sealed it with one of his trophies as the remote. Oliver eventually died of starvation, but the oblivious Lucas eventually changed the remote to the lamp.

By 2014, he was still living at his parents' house. After a storm hit the surrounding area, Lucas went outside and found a shipwrecked tanker. Telling his father about it, they went to investigate, but found only two survivors; Mia Winters and a girl named Eveline.

Meeting Eveline & the Organization
Eveline, who had the ability to produce a mold substance and control people she came into physical contact with, managed to take control of the Baker family, Lucas included, grooming them and Mia to become her ideal family. Along with his father and mother, Lucas gained regenerative abilities, even being able to grow back his hand after Jack cut it off. However, Lucas was met by agents working for Tentsu, who provided him with a chemical that stopped Eveline from controlling him. In exchange, Lucas spied on his family for them. During his time of possession, Lucas also began building elaborate puzzles within the family's old barn, some of which were certain to cause the death of the victim, even when solved.

After the Sewer Gators arrived in the Dulvey Haunted House and were confronted by Jack Baker, Lucas took Clancy Javis, the sole survivor, and put him into the Happy Birthday puzzle room. After removing his bindings, he taunted Clancy into solving the puzzle, promising him freedom if he did. However, unknown to Clancy, Lucas had rigged the puzzle to require a winder, which would spill oil onto the floor. Completing the puzzle, the cake exploded and set fire to the room. Unable to extinguish the flames or escape, Clancy died as a result. Shortly after the flames died out, Lucas came into the room to retrieve the camera, taunting Clancy, even after his death.

Conflict with Ethan
When Ethan Winters, Mia's husband, was captured by his father, Lucas attended "dinner" with his family to welcome him to their group, continually throwing food at him whilst he was unconscious. Eventually, Lucas threw his dinner plate at him, to which Jack responded by pinning Lucas' hand to the table with a knife, then removing it. When a police officer arrived and knocked at the door, Lucas and Jack disappeared, possibly to either hide from or murder him.

Whilst Ethan was investigating the old family house, he found Mia in the basement. However, before he could find a way to her, Lucas appeared behind her and took her hostage. During Ethan's investigation of the old house and fight with Marguerite, Lucas placed key cards around the family's house and the key to access these rooms within the neck of the now deceased deputy. He later captured Zoe in the family trailer as she retrieved an ingredient to a cure for Eveline's mold, leaving a severed molded head in the fridge with a note attached to it, reading "the pig is in the dissection room, bitch!". As Ethan arrived at the trailer after collecting the ingredient, Lucas called its phone and, when Ethan answered it, taunted him, telling him about his capture of Zoe and sending him to collect key cards that would allow him access to the barn. Lucas also filmed a short video, explaining to Ethan how he wanted things to stay the way they were, setting a television up to play it.

As Ethan progressed through the barn, foiling his traps and defeating the Molded, Lucas would continually mock and tease him, getting on Ethan's nerves. Once he made it to the Birthday room, Ethan, having watched a recording of Clancy's failed attempt, completes the puzzle without releasing the oil. Angered, Lucas dropped a stick of dynamite in the room to kill Ethan, but it was instead used by the latter to escape. Furious at this twist of events, Lucas flees, calling Ethan a cheater. He taunts him one last time via video recording, suggesting that he has more surprises in store for Ethan, but is not seen again afterwards. His ultimate fate is unknown.

Personality
The bright and creative inventor's mind that Lucas possesses is marred by a sadistic streak and childish immaturity. Lucas gleefully bullies and belittles "guests" of the Baker family, from throwing food at Ethan to imprisoning victims in his latest "games". Lucas promises his victims freedom should they successfully complete his challenges, but given the rigged nature of the "game" that killed Clancy, it is clear that Lucas takes too much pleasure in their agonizing deaths to actually give his victims a chance at legitimately winning and earning their freedom.

In fact, Lucas flies into a rage when Ethan places a candle into the bomb cake without first releasing the crank from the oil-filled barrel, sparing him the same fiery death that Clancy had met. Further proving himself a sore loser, Lucas then attempts to murder Ethan with dynamite, which backfires and forces Lucas to flee.

Despite his father's belief that Eveline had also seized control of Lucas, several emails reveal that he is not actually under her control; rather that he has succeeded in fooling Eveline to believe that he is. However, he genuinely revels in the regenerative powers that Eveline gifted him and rejects notions of "turning back the clock" and being fully cured, mutilating himself on-screen to prove a point to Ethan.

His evil personality is as genuine as it comes, although it is unclear whether he became evil and twisted from Eveline's influence on his family, or on his own from his childhood as a spiteful prankster, or if it is just to maintain his cover in pretending to be under Eveline's control whilst helping the third-party organization.

Lucas also seems somewhat known in the family for being lecherous. In one of the notes in the house left by his father, Jack lists off some of the newest potential "family members" they captured and attempted to convert. On the list, Jack mentions that Lucas brought three college girls, but that they could not be converted due to being "rotten", berating Lucas for being an idiot. In another note that Jack addresses to Lucas, he mentions that he is free to do whatever he wants with Travis' girl. During the barn fight, Lucas also mentions to Ethan that he really needs a girlfriend, and asks Ethan to find him one.

Abilities
Just like his parents, Lucas has incredible regenerative abilities, being able to regrow his arm after it had been sliced off by Jack, with Lucas implying that this wasn't the first time it happened. Despite his superhuman abilities, Lucas never directly confronts Ethan or chases him around the house, instead preferring to rig up elaborate traps and "parties" for his victims while taunting them via video recordings.