Sullivan has escaped the Safe House and is fleeing Fortune City with the evidence that can clear Chuck's name. As the player enters the maintenance area in Royal Flush Plaza a countdown shows up on screen labeled: TIME UNTIL FIRE BOMB. A cutscene after the player exits the maintenance hallway shows Chuck running out into Royal Flush Plaza, calling Stacey, and telling her that he's lost Sullivan. An urgent message from Stacey eventually comes in on the transceiver, telling Chuck that she saw Sullivan heading for Fortune Park. If the player is beyond this, a message comes in, telling Chuck that Sullivan is trying to break open the locked elevators in the Yucatan Casino.
Chuck must travel to the Yucatan, find the open elevator located in the back near the restrooms, and take it to the roof. Exiting the elevator, Chuck is just below the rooftop where Sullivan is escaping. The player must move through the zombie infested room, up the stairs, and outside. A cutscene follows of Chuck confronting Sullivan, who is suiting up for a surface-to-air recovery or a Skyhook.
After the cutscene, the player must defeat Sullivan, who stays on top of the scaffolding and throws down flares which serve as targets for the plane's missiles. Sullivan also has a handgun, which he will draw when Chuck is near. If Chuck is on the scaffolding, Sullivan will fight and charge him with his bare hands. If the player attempts to attack Sullivan with a melee weapon, Sullivan will grab Chuck slam him to the ground. The equipped weapon will fall out of Chuck's hand and off of the scaffolding as well.
Upon defeating Sullivan, a cinematic shows the plane firing upon Chuck, who falls down next to Sullivan on the scaffolding. As Sullivan stands, Chuck attaches a carabiner, which is mounted to a railing, to Sullivan's belt. The plane hooks the balloon and Sullivan is killed. Chuck calls Channel 6 Action News and offers "the scoop of a lifetime" if they send rescue helicopters.
The helicopter comes and rescues the survivors in the safe house. Nobody has seen Chuck's daughter Katey, however, so Chuck goes back to the safe house to look for her.
Chuck enters the deserted Safe Room and only finds Katey's backpack. 72 hour mode ends and the credits roll.
Sullivan is by far the most dangerous enemy Chuck faces in the game, as he not only has an immense amount of health, powerful melee attacks and a Handgun for a sidearm, but any attempt to use a melee weapon on him will result in Chuck not only being disarmed (note that Sullivan is unable to disarm the Tenderizers or the Knife Gloves) but flung from the platform where the battle takes place. This means that with exception to using the two weapons he cannot disarm, combat must otherwise either be hand-to-hand or with ranged weapons.
Go to the maintenance room and create a spiked bat with the Box of Nails and baseball bat in the room. Exit the maintenance room and go to the room opposite and grab another box of nails and a sledge hammer that is further along the hallway. Make another spiked bat and a defiler by combing the fire axe and the sledgehammer.
Proceed to the right to Americana Casino to Shots & Awe in the center of the casino. Wine and Beer can be found here in infinite supply. Combine both for two or three quick steps, which can be used for health and too speed up Chuck.
Another LMG can be found in the Yucatan Casino atop the slots in the center.
Make sure you have at least four fire arms before you enter the Yucatan elevator and at least two health items. The rest should be melee weapons.
Sullivan will throw flares in Chuck's general vicinity if he looses sight of him, which act as targets for the AC-130 gunship's bomb fire. The resulting explosions will blow holes in the roof, clearing many zombies, but also posing a falling hazard. If Chuck falls in, he will be injured and have to fight his way past hordes of zombies to return to the roof.
If Chuck is close to the scaffolding, Sullivan will draw his seven round handgun. Sullivan is a crack shot with his Handgun which is powerful enough to drive Chuck backwards with each shot. He fires off a round and then the rest in twos. Sullivan takes a few seconds to reload, giving Chuck ample opportunity to shoot him.
If Chuck climbs onto the scaffolding, Sullivan will put away his handgun and fight Chuck with his bare hands. He will charge Chuck, jab at him, and kick him. After charging Chuck, Sullivan has three sets of attacks he will cycle through before charging again:
If Chuck keeps a distance, Sullivan will only charge.
If Chuck attempts to attack Sullivan with a melee weapon, Sullivan will body slam him and the weapon will be thrown from the scaffolding, sometimes through one of the gaping holes in the roof.
Sullivan's kick will throw Chuck himself from the scaffolding.
Try to move all the food and drink lying around into the kitchen area down below so the AC-130 plane does not blow it up.
Chuck cannot normally hit Sullivan with any melee weapon, or else Sullivan will disarm Chuck and throw him. Sullivan often throws Chuck off the platforms, causing damage to Chuck, and Chuck runs the risk of being knocked into the zombie filled craters being blasted into the ground by the rocket attacks. While Chuck is on the ground, he is open to pistol fire, rocket fire, and the occasional zombie attack. To avoid being knocked to the ground, he will need to roll to evade his attacks, and then time his attacks. Further, Hand-to-hand combat will be immensely difficult if Chuck has not practiced the numerous unarmed combat skills.
The best attack against Sullivan is the Elbow Drop. (Jump then hold R2 / RT + Press / ). Chuck will damage Sullivan, and during the animation in which Chuck stands, he appears to be immune to attacks. Run towards Sullivan, and perform the move. As long as Chuck doesn't perform the elbow drop while Sullivan is rolling, he will his and damage Sullivan.
Double Drop Kick
Chuck's Double Drop Kick will not only inflict similar damage to an average melee weapon, but will also stun Sullivan long enough for Chuck to regain his footing. The Front Kick will put Sullivan on his knees if he is not in his punching combo or rolling animation, permitting Chuck to strike Sullivan with melee weapons that are swung low such as the Defiler, Sledgehammer, or vertically such as the secondary attack of the Spiked Bat.
The Double Drop Kick can also be used with the quick step and Sniper Rifle. Use the Double Drop Kick on Sullivan until he falls to his knees. Now aim at his head and shoot several times before he gets back up. Repeat until Sullivan is dead. Using an LMG takes a fair amount of time, but a few shots after stunning him allows Chuck to kill him solely with the LMG.
The Haymaker (hold Square or X) puts Sullivan on his knees. Follow up with a melee weapon (the Defiler works best), the sweep kick, or a gun.
Also Chuck can kick him normally then punch three or four times then repeat.
If Chuck climbs the scaffolding and activates Sullivan's hand-to-hand combat, he can use the Front Kick skill (+) on Sullivan. This will knock Sullivan to his hands and knees, allowing Chuck to use the downward attack of a a Fire axe, Sledge Hammer, or Defiler on Sullivan.
Melee Weapon Tactics
As mentioned above, Sullivan is unable to disarm the Tenderizers and Knife Gloves, making them desirable weapons if the player doesn't feel comfortable using unarmed or ranged tactics. The Knife Gloves should be used over the Tenderizers as they do more damage; they can be made from a Bowie Knife and Boxing Gloves, both of which can be found easily in Royal Flush Plaza. With an abundance of healing items, it is possible to "tank" most of Sullivan's attacks and beat him down using the Knife Gloves, retreating to the foot of the scaffolding when necessary to heal.
Ranged combat presents an entirely different set of difficulties. The area is filled with zombies, meaning care must be taken to prevent attacks while preparing to attack Sullivan.
Shotguns and Handguns deal too little damage to be effective, but Sniper Rifles inflict a fair amount of damage, as does a fully-loaded Six-Shooter. The six shooter is the only ranged weapon which can defeat him by itself.
The area provides minimal cover - the only objects which will block Sullivan's revolver fire are four pillars circling the platform.
In front of the entrance to the roof is a divider that Chuck can hide behind. From here, he can safely shoot at Sullivan, who's flares are out of range. This requires several powerful guns and a lot of food.
Between the scaffolding Sullivan stands upon and the shorter section used for getting up there is a gap where Chuck can hide. Sullivan will continuously shoot his handgun, but will never hit Chuck. After seven rounds, there are a few seconds to shoot at Sullivan, before Chuck needs to hide again.
Chuck can also throw objects and weapons, such as the defiler to injure Sullivan. This requires constantly retrieving it however.
It is somewhat difficult to range attack Sullivan, because there simply is not any place safe to snipe him from. There are zombies all over, and to make matters worse, rockets will fall on Chuck, knocking huge chunks off his life bar. The blasts also knock Chuck off his feet, leaving him open to Raymond's heavy pistol (which does one block per hit). If Chuck wants to shoot Sullivan to death, he can take cover behind the planter wall, and with a little luck and some fancy shooting, he can whittle him down, especially with the Six-Shooter. Avoid the flares he throws, as the AC-130 plane tends to drop explosives on that area - however, the AC-130 is extremely good at clearing areas of zombies that give Chuck a slightly safer point to shoot from.
The best tactic to beat Sullivan is to wait for him to blow a hole in the ground (or blow a hole yourself). Then find a place underground where Chuck can see him and the zombies cannot reach Chuck and shoot him with a sniper. This tactic will take at least two sniper rifles, even with perfect hits.
The ideal ranged weapon to engage Sullivan with is the Six-Shooter. Always stay in cover and do not attack him when he rolls, which he will do after being shot around three times. During the roll and momentarily after, he is invulnerable. Keep track of his health bar-if his health bar is not above him, don't fire.
The ideal spot to engage him from is the wall in front of the staircase doors, only stepping out to shoot him, allowing a perfect spot to pop out and shoot him, and then retreat to cover. Explosives will not damage any of the environment in this area. Additionally, the zombies around this area are few and can be eliminated with ease, allowing good mobility from within cover. Executed properly, Chuck can defeat Sullivan without taking any damage.
Chuck can also use the Six-Shooter to defeat Sullivan directly under the platform. If Chuck runs to the box under the middle platform and hugs the edge closest to Sullivan, Chuck can get a clear shot at Sullivan as he moves to the side, but he cannot shoot Chuck from here and the zombies cannot harm Chuck on this platform. Stay aiming on the left spot of the platform and he will constantly go there and Chuck can fire at least 2-3 shots on him before he moves away and returns to that spot.
Chuck will use Sullivan's discarded transceiver and call for help. The firebombing is subsequently withheld in order to carry out a rescue. When Chuck arrives back at the Safe House, he finds no sign of Katey or Stacey. Instead, he is greeted by the sound of TK taunting over the transceiver. This ending leads into Overtime, which will then begin after the credits.
Chuck completes all cases and gives Katey her Zombrex, but doesn't give any Zombrex to TK. Like ending S, Chuck returns in a helicopter for Katey and Stacey, but as he goes to retrieve Katey's dropped backpack, he is pulled into an elevator by the zombified TK. He orders Stacey to leave him, and to look after his daughter. As the choppers lift up, Chuck is seen holding off the zombies in the elevator. His fate after this point remains unknown. This is the only A ending in the series to be the true ending, as it leads directly into Case West with Chuck fighting off the zombie TK.
There is a glitch that can occur when fighting Sullivan. If Chuck happens to be hit by a missile from the plane above, he can be thrown off the building and land in the space below the area the fight takes place, which is nothing but the sky texture, with no way get back up, forcing the player to load or quit.
The plane sending missiles onto the rooftop may cause several gaping holes in which any zombie killed in the area will lie dead as if there was a floor, making it look like the zombie corpses are floating.