I found a useful walkthrough for creature creation here: http://daanhendriks.co.uk/sound-design/creature-sound-design-tutorial/
The enemies i've chosen for my game are the Hellpig and the Bauul, so i can attempt both small and large creature sounds. I started with the Hellpig by recording some short, snappy and snarly sounds for its bite attack. The sound file below plays my chosen sounds individual and then the final layering i made.The screenshot shows the audio layering i made from these sounds, as well as the folder organisaion i used to seperate the various stages in the sound design process.
I bounced these raw layers to a new track and then duplicated them three times. My goal here was to create main body of the final sound by arranging the three files at various timings, amplitudes and pitches, until they sounded like one cohesive sound.
I duplicated the new mixdown to three more layers: Rasp, Body and Growl. The Rasp layer was to contain the high end snarly content. I did this by high passing and distorting the sound. The Body layer had a small amount of flanging added to it. The growl layer was pitched down ten semitones and timestretched to be 40% slower. I also ran it through some chorusing and delay to widen it slightly. Finally i sent all the tracks to a reverb and recorded the reverb channels output. I then blended this file in with the others to act as glue. I created a group auxiliary and added a limiter to finalise the sound.
The grunt SFX were made using the same method but implemented differently. I exported the Rasp, Body and Growl layers independently and put them into a blend container, each with their own pitch and volume randomisation. I used the same three sound files for the Grunt_Hellpig, Death Hellpig and Pain_Hellpig events, which saves a lot of work and a lot of memory. The in-game result worked really well.
For the Bauul i used the finalised Hellpig sound, layered it three times again but pitched it down lower. I also added a breath layer with the reverse reverb recording. The layers were again kept separate in Wwise for a lot of variety.