When team of zombie fighting monsters lose their commander an overzealous commando orders them to protect a solitary human that could save their food source from extinction.

Its a nice and definitely original idea - zombie-fighting monsters (which still feeds on humans) needs to save humans or they will extinct (not enough food). But I have to agree that the logline is very, very unclear and complicated.

Perhaps it would help to put only the important information and then make it a logline.

Like: Commando - needs to save human who is a cure (cure against zombie plague i guess?) who is likely to be eaten by zombies. So its a triangle - monsters, humans, zombies. Not sure if its important that they had lost their commander.

Overzealous does not feel much as a perk, but it perhaps intrigue a comedy? What about starving? It actually adds up on irony, that starving monsters needs to protect their food alive and it can generate a lots of comedy-tension like situation.

From all of it I would build the following:

When zombies ate all human food source, a breed of starving monsters needs to protect last living woman with a cure to the plague, or they have to face the extinction.

I know that I have turned it upside down, but hopefully it will help you somehow to find a way to communicate the story in more simple way ;)

It is a very intriguing logline and yes it is a little complex but I think that adds to the point. I already know what genre and tone to expect from the words used in the logline so I think that works well. Richiev's point is right but that is just a rearrangement or punctuation check that is needed so no big deal. The line works well.

Thanks!