William "Billy" Yoder was a mercenary soldier, a member of the mercenary group InGen sent into Jurassic Park during the Isla Nublar Incident and was the deuteragonist in episode 2-3 of Jurassic Park: The Game turned to the main antagonist in episode 4.
At some point during the game Billy and others in a group of mercenaries are hired by InGen to retrieve and rescue remaining Jurassic Park staff on the island. Upon arriving, he finds Nedry's jeep and has a run-in with a Dilophosaurus. Soon after, he begins rounding up the survivors. He meets a female employee, who informs him of the shocking events that happened at Jurassic Park.
Along the way he and the mercenary group meet the Hardings: Gerry, Jess, and the smuggler Nima Cruz. At first, he is sympathetic towards the dinosaurs, ordering Oscar not to kill a Dilophosaurus that he had wounded. But as time wears on his respect for them wears thin after seeing them kill his friends. He develops a rising resentment towards Laura Sorkin's motherly devotion to the dinosaurs, often contemptuously referring to them as her "freak show" or "pets" simply to spite her, and taking great care to emphasize that they will all be destroyed in the Napalm bombing. His dislike for her rises continuously after Oscar's death, and when she quietly reveals that she had known about the Troodons, he threatens to kill her, only to be stopped by Dr. Harding and Jess - but not before forcing her at knifepoint to admit that everything had all been her fault.
After the deaths of his two best friends, he goes insane. He decides to take the Barbasol can for himself, so that he would be paid for the embryos. In the end he betrays the group and fights Nima. Billy doesn't hear the incoming T. rex, yet he manages to stand still. But Gerry, deciding to shift the tyrannosaur's attention to the enemy, kicks the barbasol can so that it would fall into the water. Billy ran after it and managed to grab it. After he gets up he only feels the breath of the Tyrannosaurus behind him before it devours him.
Episode 2: The Cavalry
Hired by ingen billy yoder ,Oscar Morales, and Danny /D-Caf was sent to rescue the remaining survivors traveling on a helicopter to meet a already dispatched team bravo to the visitor center but found Vargas the sole survivor gone crazy attack his team try to kill them but to him down with Oscar finding a mysterious poisonous but hallucinating him to attack billy check the video and saw the earlier footage of Nima marching Gerry and Jess out of the building at gunpoint the pack of dinosaurs attacked and dragged Vargas away returning to the helicopter seeing the smoke by them to call for help and Jess Harding try to contact with the radio but Nima caught her and kept moving going towards the direction and attack by a Pteranodon causing a emergency landing with yoder piloting since D Calf got knocked unconscious and landed with d cafe reaping the helicopter billy and Oscar went looking from the mand split up encountering a angry mother Dilophosaur protecting her eggs hold her off until oscars scared her away locating and disarming Nima and rescuing Jess and Gerry from falling off the track of the bone shaker returning to the helicopter with d caf gone finding his helmet he never left behind making Oscar fix the plane while yoder tested and piloted the copter and found the right battery before takeoff before they got eaten by a t rex heading to get Dr. Sorkin from her lab but refuse to go because she wants to care for the herbivores dinosaurs Dr. Sorkin sent Billy, Oscar, and Jess to load the copter with files digging through Jess found rejected proposal for a animal preserve allowing billy convince her by exploiting her desire for Isla Nublar to become a wildlife preserve for the dinosaurs now choosing of go but want to get the water supply supplied with the cure for the Lysine contigancy with Jess and Gerry but Nima got free and try to escape but Yoder and Oscar reached the copter in flight yoder piloted and Oscar battles Nima but in battle but ended up with the knife entering the controls cause them to crash hitting the water tower and crashing nearby while Jess, Gerry, and sorkin were getting the parasaurs out of the pen but attacked by velociraptor they went to the damaged water tower.
Episode 3: The Depths
Nima billy and Oscar survived but lost the chopter and guns Nima unconscious Oscar scout the area yoder salvaging the wreckage Oscar returns to tell about the leaving T. rex Oscar found the raptor ans saw them open the doors to the separate part of the tunnel where sorkin Jess and Jerry's were hide billy discovers the dino embryos in the shaving cream can Nima conscious again being forced to split the profit for the embryo they hid from a T. rex chasing a parasaur but got away but the T. rex found them and made them go to the tunnels which Oscar have entered but billy dropped the embryo and had to recover them from outside which the T. rex was eating entering the tunnels further Nima saw the glowing yellow eyes in the shadows seeing them from a dino that bit her in the beginning episode billy remember the eyes from the visitor center which took Vargas refusing to continue he tried to get the main lights on by using the power pannel but was confused with the circuit controls shutting down the emergency lights but got power back and met Oscar who killed a raptor on Simgle combat billy then made Oscar agree to help deliver the embryo but continue with the rescue mission they met up with the others battling a pack of raptor pipes bursting sorkin explains that the power plant will explode drstroying the island and convinced them to help after it shut down a fail safe activate causing gates to close the exits but after the raptors enter I control to open it malfunction with the only control down on the main floor Oscar sacrifice him self to open the gates billy sad about his loss they went to a boiler room locking them inside the raptor left for being afraid of some thing they find d caf buried in a forest like nest with him brain dead and eggs laid into his abdomen affected the poison used on Vargas and Nima sorkin recognizing the nest from the Dino that was supposed to be destroyed but she couldn't do it angered billy bulled out a knif threatening to kill sorkin for not destroying the Dino that kill the bravo team and D-caf
Episode 4: The SurvivorsGerry and Nima convinced billy to let sorkin live but made her admit it was her fault making the recent past bygones Jess found a lock gate to a tunnel sorkin reveals to be trodoon that was the Dino and tells about the working phones online at the visitor center but was to far away the only one left was the marine exhibit but the trodoon have returned but they escaped using flares which keeps them away broke the lock and escape through but before billy took a grenade from d caf they went through the gate but gotten lost but found blue prints which lead them to the marine exhibit but encounter trodoon hoards and gotten separated billy Jess and sorkin got to the tunnel which leads to the marine exhibit and waited for Nima and Gerry who was taken back by the automatic car sorkin left on at the beginning but the phones only work in the control center underwater billy rushing then and explanes that the us navy plan to bomb the island into the sea Nima angry for the island was her home until ingen took over sorkin went to the control center and lock the elevator after unlocking it and got to the outer dome of the control center sorkin trying to stop the bombing she then threatening by keeping them hostage billy used a axe to open into the interior as she released the mosasaur as it charged the center knocking sorkin into the pool at the mosasaur eats her billy orders to continue as he and Nima was goanna use the boat that has the collector for the embryos and allowed the us navy the proceed with the bombing. billy then try to kill Gerry and Jess because with no men left he only cares about delivering the embryos and getting the payment but nima disgusted by Yoder's betrayal, refuses. Yoder throws the grenade as he escapes to the surface, which cracks the facility's windows when it goes off, causing water to seep in. As the elevator ascends, however, he realizes that the embryos are gone, stolen by Jess while he wasn't looking after using scuba gear and escape the mosasaur through the cave they arrive at the dock seeing the boat but nobody around thinking of a dino eating them then Jess made a joke about billy eating them and billy attack then knock Gerry unconscious as Nima and billy fight but almost lost as billy kick the embryos to Gerry who getting conscious back as the and talks about the deal before the Tyrannosaurus rex approaches through the main gate they all froze because of it can't see then if they don't move Gerry gently pushes his foot making the embryos roll to the ocean distracting the t rex but Yoder rushes for it, giving himself away and caught it but as he gotten up he felt the T. rex breath ands turns around as T. rex notices him as he didn't freeze and gotten devoured loosing the embryos.