Throughout the game, there are a total of six bosses that Vince comes across, from a giant stone statue of a woman to a toy doll. These bosses have been brought to life by Kosmo using zombie dust and Vince must defeat them in order to continue on with the story.
This boss takes on the form of a giant T-Rex that Kosmo brings to life after Vince arrives in The Quarter's museum. This boss can be defeated by subjecting Vince to a lightning strike, which in turn will destroy the Bone Goliath. First Vince has to obtain a helmet (while avoiding the Bone Goliath's tail) with 3 electric receivers on the top, to help with the lightning strike. Then Vince has to make his way to a lever on the second floor whilst avoiding the Bone Goliath from chomping Vince to pieces to open up 2 glass skylights on the second floor. Then Vince will have to go further along the 2nd floor to find another lever that opens up a hatch near the entrance to the museum, which then Vince has to go to the hatch and get struck by lightning to kill the boss. From there, there is a tunnel underneath the Bone Goliath where Vince can continue to Roachfort.
It's a two-headed cyclopian alligator that Vince fights in Roachfort after getting everything for the air balloon only to be thrown out of the air balloon by Professor Ethel. Vince describes it beforehand as "the obligatory boss battle." He kills it by jumping into a spike pit three times. After defeating it Vince heads to Crypt City.
Vince enters the Crypt City mausoleum and gets put onto a rat by Kosmo. Kosmo then zaps the statue in the center with his magic, bringing it to life. Vince also wearing a cowboy hat dodges the statue's attacks and destroys it by getting crushed by falling debris three times while riding on the rat. Vince then heads to Brusque Manor after it crumbles.
Vince arrives at the Brusque Manor and meets Dolly who starts out friendly but attacks Vince after Kosmo pulls the string in her back. Vince kills Dolly by getting crushed by trains three times before moving onto The Bayou.
Vince arrives at the Bayou and gets all the ingredients for Crawdad Jimmy's gumbo. Kosmo then appears and creates Hurricane Hannah with Crawdad Jimmy's gumbo. It attacks Vince by throwing objects at him. Vince defeats it by jumping into a windmill three times. He then heads to his final destination to rescue Madam Charmaine which is the Carnival Deprave
Vince arrives at the Carnival Deprave and fights Evil Vince in the house of mirrors and describes him as "the obligatory evil twin." Vince avoids Evil Vince's attacks and punches him three times after Vince defeats the monsters who are first, Pit Frogs, then after the first punch, Imps (most are yellow) and then, Crab IIIs last. As Evil Vince perishes Vince says "Sorry, pal. There just isn't room in the world for two handsome devils like us."
The final boss of the game which is much more elaborate than the previous bosses. Vince finally gets into the Carnival Deprave's Big Top and sees the huge Kosmobot which makes Vince run away in fear wanting to get out of the big top but Madam Charmaine encourages Vince to move quickly and look for his openings. Reassured, Vince sends himself flying into 3 targets with the use of a bumper car while dodging the Kosmobot's stomping causing the Kosmobot's legs to stop working.
Vince then goes through a door in one of the Kosmobot's feet and climbs up the huge robot while avoiding its arms and eventually getting to a fighter plane. Kosmo starts firing rockets at Vince from his robot which Vince dodges with ease and shoots the target in the Kosmobot's mouth with the plane's machine gun about 4 times unlike the other bosses which only required only three hits with the exception of the Bone Goliath boss which only required one hit.
The Kosmobot stops functioning all together and opens up a entrance to the head of the robot allowing Vince to go in it. Vince flies inside the Kosmobot and makes his way up to the robot's brain avoiding the vortex moving up while destroying himself using the 3 methods to destroy the brain like getting smashed by a hammer and getting smashed by cymbals a monkey is holding then finally getting buzz sawed into pieces by none other than a buzzsaw right across from the brain itself. Steps appear for Vince to get up to the brain and hits it to get a skull which Vince then activates his Voodoo Powers which is him shoving his pin into his head making the brain blow up finally destroying the robot and saving the day but Vince forgets about Madam Charmaine and quickly heads back to get her only for her to get angry at him for leaving her behind.
Kosmo makes one last effort to destroy Madam Charmaine and Vince once and for all by throwing his last amount of Zombie Dust at her but she easily deflects the attack calling him a silly man and threatens to show him what real magic is with Jebs saying to his boss that she's kindof mad only for Kosmo to call her bluff which she admits she has no more dust but Vince does which he readily gives to her. Madam Charmaine then launches the zombie dust at Kosmo and his henchmen turning them into balloons and Vince replies saying "I always knew he was an airhead." Vince then takes his pin and shoves the pin into his head again saying "Now this will be fun." which makes Kosmo and his henchmen pop making them fly away. Vince and Charmaine then begin the journey home.