Giant Goo:
Super large goo, drops normal sized on taking damage. Slow, but once it’s sighted a player, slowly builds up speed as long as it goes in a straight line - it’d be awesome if it could take up multiple tiles like a vehicle, have trouble turning, and crash through buildings then explode into multiple goos, but that seems a bit much.
Zs:
Juggernaut Zombie - slow, but stupidly armoured and healthed, basically to be a threat to vehicles if they crash into them.
Leaper zombies - basically hunters from L4D, zombies that leap like cougars at you.
Frozen Zombies - inflict frostbite on hits, put fires out around them
Hurler Zombie - size of a hulk, but not as fast or tough, instead throws other nearby zombies at you.
Horde magnet - some form of zombie that attracts others to it, uses them as shields, and heals them.
I’d like to see brutes get a bit of an upgrade, and have tanks take on the role you described for juggernauts. They can already go through buildings, why not be able to knock cars aside too? Tanks also already attack anything in their way, maybe they could get a special attack to sometimes throw whatever they run into at you, whether it’s a two-by-four or another zombie.
Necromancers already hold back from the fight and resurrect stuff, so I don’t really want to see ANOTHER healer, and shirkers already attract more zombies like hoard leaders; especially since they’re faster.
What I really, really like about your post is the idea for larger monsters. A massive slime that can smash into buildings and throw off a dozen smaller goos? Awesome! Evolved Triffid queens that start using the plants around them as a thorny form of locomotion and damage? Great! Giant spiders with no upper growth limit that eventually take up more space than your average bus? Freaking cool! Dinosaurs? Yeah!
(Seriously. Dinosaurs. Come on.)
Also, this would give us a practical reason to ram something with a bus and into a gas station. Not only is it two of the four shark deaths from Jaws, it would be an actual use for a city-block-consuming fireball.
I’d like to see meta-creature… I believe you all are familiar with the movie “The Thing” - something that can transform other beings to be “The Thing”, much like alternative infection - but these things would go and try to form a bigger creature instead of being separate creatures. So it would infect and assimilate biomass to become larger - be that zombie, wolf or triffid.
“Hurler Zombie - size of a hulk, but not as fast or tough, instead throws other nearby zombies at you.”
I’d like to see normal zombies throw stuff at player, not as serious thread but just as a nice touch. Hurler would just throw larger stuff, a lot more often and somewhat more accurately.
Idea is good, especially if Zs and other stuff thrown gets damaged in the process. You could use hurler to get rid of mobs by baiting it to throw Z’s at you while standing in the trapped zone. Every now and then these living dead missiles would break and player would be showered in bodyparts instead of intact zombie. Every now and then boomer is picked up and tossed at player. Every now and then hurler picks up a player and throws him to other hurler…
Yes. that would add at least +2 to the fun factor.