For Propellerhead Reason 3 and 4 Melodiefabriek has created many sounds which are included in the Factory SoundBank that comes with the program. Melodiefabriek has created over 270 patches for the program. Also several samples/sample-loops were licensed for a lifetime to Propellerhead Sofware.
For a complete list of the patches Melodiefabriek has created for Reason 4 see this list.