[Gretin]

If I understand the place you are talking about, you have to use the switch to squash the slig who's closest without getting shot by the one in the background. See the picture attached. After you've killed the close slig, you just have to run past while the slig in the background and possess the slig on the next screen. You then have to activate the flint lock with the switch, which will set a bunch of slogs on you from the kennel, so you'll need to be ready to shoot. Once you've finished with them, take the slig to the right and quickly shoot the other slig. That's pretty much it, the rest is easy.