The Facts | Main missions Dead Rising 2 Guide
Last update: 11 May 2016
Goal: stop Sullivan.
Location: Yucatan Casino Rooftop.
In order to complete the mission, head to Yucatan Casino and ride the elevator by the toilets onto the roof. Once you fight your way through the band of zombies, open the door, watch the cutscene and begin the fight with Salivan. It's definitely the hardest fight in the game, so it's worth preparing for it properly.
You will need: 2x healing potion, 2x food portion, LMG and one hand weapon. You can get the food at the casino restaurant, the LMG can be found in three places: on Yucatan Casino roof, at the pawnshop in Platinum Strip or at the pool in Palisades Mall (in the bushes, by the middle of the slide). Once properly equipped, save the game and move out.
Right after the fight begins, run to the middle of the location and climb up the scaffolding [1]. Even though your enemy is completely invulnerable to hand weapons, you should try keeping one of them equipped throughout most of the fight. It's because sometimes you let go of your weapon once getting hit and you'd surely want it to be a baseball bat, not an LMG. Once you're upstairs [2], keep running around the boss until he rolls backwards. To a quick dodge and then kick the enemy by holding down R2 and pressing square. This way you will stun him and will be able to shoot him freely with the LMG (without aiming, you just need to be facing him), but stop when only the enemy stands up. Otherwise he will perform a very powerful and hard to dodge attack.
Definitely the hardest part is hitting the boss with the mentioned kick, but there is luckily an alternative. Instead of kicking, you can try to hit the enemy with a different attack. Execute it by jumping and holding down square once in the air. It requires a high enough level, but you should have it at this point in the game. If you lose too much health, patch up either downstairs by one of the tower's walls or upstairs right after the enemy does a somersault. Sometimes the boss can knock you down and you might get trapped inside the tower. Unfortunately it's a bug and the only way is to restart the game. After repeating the kick and LMG action a couple times the enemy should finally fall [1] and a cutscene will play [2].