Put this clip at the start of the intrusion, right after the person walks in, then follow it with Oh Brother This Guy Stinks to dismiss the intruder, and finish with Ba Dum Tss if you want the scene to end as a joke.
About this sound
A gruff male voice delivers the line 'What are you doing in my swamp?' in a short clip of about three and a half seconds, sounding annoyed and territorial as he confronts an intruder. It feels funny and confrontational, like catching someone somewhere they do not belong. The line comes from Shrek, spoken by the ogre to Donkey when he first enters the swamp.