In Merlin season 3 episode 4 33 minutes and 40 seconds is the sound effect for someone being hit the same as the one used in for an orc dying

I'm not sure but I love that show Merlin until they took it off NBC I think it's on the sci fi channel now or something. The sound effect was probably the same one because most studios if they don't have a foley stage will use public domain sounds which are open to anyone.