Being a feral cat, he is all about territory and pecking order. You should wear gloves and boots and jeans when you go out to feed them, have a squirt bottle full of water in your hand, look him square in the eye with a bland expression and go about your business feeding the cats as if nothing were amiss and don't show any sign of fear if he starts with his hissy fit stuff. If he advances on you, just squirt him with the bottle of water; he should back off and will probably run away. Don't worry, you won't harm anything but his kitty ego, and he will be back, and he will have a healthy respect for you when he does. You just need to remember who is bigger and show him who is boss and he will settle down. I have ad problems with cats like this who actually attacked me, but I tend to be rather fearless with cats like this, having dealt with cats all of my life. I've been bitten and scratched and chomped and jumped on, you name it, and cats who jumped on me were firmly grasped (with gloved hands) and lightly tossed away without hurting them. A few times I still had some sizeable bite and/or scratch marks on my arms that ran with blood and had to go get tetanus and rabies shots as a result, but this is the reality of the situation when you take care of wild animals. Anyway, they all landed on their feet and they all ran for the hills, but they all came back a week later, meek and mild and wanting to be fed.