The dfference between an original disc and a pirated disc? Well, an 'original" would be one you get at the store or online at reputable sites (such as our Amazon.com affiliate store). A "pirated", meanwhile, is one that was copied and sold illegaly.
Now then, the creature at the end of the level: the purpose here is to get to the sword segment above, not kill the creature. Just run around the room and use the four levers between the small electrified orbs on the walls. Each time you use a lever, a hook releases a big orb above the Tesla gun. When you pull of all fours levers, the big orbs and the sword segment lower. Run to the Tesla gun and use it. You need to push the big orbs towards the small electrified orbs on the walls. Every time you do that, a blue energy shield appears on both sides of the big orb, the latter of which stays to this position for a few seconds. You have to push all four big orbs and make them stay at this position at the same time. The shield that protects the sword segment above will shut off and you have to jump off the gun and use the Grapple to take the sword segment from above. If the creature gets in your way, fire some electricity to make it leave for a while. When you do that, a cut scene plays and the level is over.