Might as well add in some of my own ideas.
Obviously we have a couple from my last thread, but hereâs some more zombies 
[T2] Digger Zombie: A feral zombie that has grown longer claws able to dig through the ground with ease. Much like the Giant Worm, this zombie will tunnel through the ground to reach you. (if possible)
[T2] Tentacle Crawler: This crawling zombie has sprouted gooey tentacles enabling it to crawl at a faster speed, as well as immobilize you with them or even disarm you.
[T2] Combustion Bloater: A bloater that has gained flammable properties to its goo. Killing it with bullets, flame, or heated weaponry will cause it to explode, and is overall not recommended. This Bloater shoots out goo at an accelerated rate causing it to catch fire and turn into a fireball of sorts which will burn the ground. (inaccurate attacks)
[T3] Combustion Bomber: Same as the Combustion Bloater, only any weapon will immediately cause this bloater to explode. Its AOE range is also bigger, and its fireball is slightly more damaging.
[T2] Injector - Trait: Zombie gains a bonus chance of infecting you.
[T3] Reverse Mosquito (Normal Zombies only): This zombie has grown a large proboscis where itâs nose once used to be. It will attempt to inject you with a high concentration of blob/zombie virus. (whatever you want to call it). Infection chance is extremely high. This type of zombie has a hard time piercing through armor.
[T2] Unpredictable Stumbling - Trait: Zombie gains bonus ranks in dodging by shuffling side to side and bending in an unpredictable manner.
[T3] Vibration Dodger - Trait: Zombie gains a large bonus in dodging by swinging wildly in an incredibly fast way. In fact its swinging so fast that your eyes are having trouble keeping up with itâs body movements. This Zombie can even dodge bullets. (though less so)
[T2] Rampaging - Trait: Stuns barely even affect this zombie. It just keeps coming.
[T3] Unstoppable - Trait (Brutes and Hulks only): Stuns donât affect this zombie, and knock-back is practically useless⌠Furthermore this zombie will plow through most terrain obstacles with ease, never losing speed. You better have a plan before taking these guys on.
[T2] Essence Stealer - Trait (Master only, extremely rare): This Master zombie will repair itself partially whenever it attacks (and hits) you. Additionally, upon reaching low life the Master zombie will try to escape. If it succeeds, it will try to find another zombie to eat, gaining all of itâs (useful) traits as well as repairing itâs body to full. Kill this creature on sight, for if you donât it will just grow stronger and stronger. (If it were to find a hulk and eat it, well thenâŚ)