When Rick set them up, they were just plain Ethans, so had Transform and Animator components only, in this video they have controllers etc, from the 3rd person setup… However, if I change to using those my mobs now run around when my character does, but without it they dont get seen as enemies… I didnt see anything in any of the portions where that change to the enemy prefab happened.
At the previous episode Ben changed some things, including the enemy prefabs. Pretty much take a fresh 3rd Person controller prefab from the Standard Assets, assign it the red enemy material, and remove both the Third Person User Control and the Player Movement components (second one only if you overwrote your prefab).
With that done, replace the old enemies with the new prefabs. Same for the big guy, for which you’ll need to make another sepparate prefab. :^)