The Boomer is 3-block wide (excluding arms) zombie. It can eat and spit up blocks. Attacks player on sight. Low health. Can appear in day.
The Hunter appears to be an exact copy of the player or a villager. However, it walks on walls. It will pin you down and extract claws and slash at you until you die. Attacks player on sight. Low health. Can appear in day.
The Smoker has six tongues that destroy blocks and health. Its tongues hang out and it is covered in cobblestone armor. His weakness is that when his tongue is out, he is paralyzed. Spawns from behind the player and attacks. Can appear in day.
The Tank is a 5-block high zombie with huge arms and fists. It only attacks players with below half health. His punch can send you flying up to 50 blocks away. He can pick up structures and throw them. It dies instantly when shown fire. Appears at night, but still lives during day. Has high health.
The Charger is a zombie with one bloated, thick arm. It will try to ram you with this arm. If it hits stone, iron, diamonds, gold, or obsidian, it dies. If he rams the player, you will go flying up to 30 blocks away. Has high health. Attacks player on sight. Can appear in day.
The Jockey will jump on you and ride you, forcing you to ram into things. Will jump on you on sight. Appears in day.
The Spitter is a 5-block high zombie. It will eat blocks and spit them out as lava that never stops growing. It has very low health. Attacks on sight. Appears in day.
The Witch appears to be a female version of the player. Provoked by touch or light. Very high health. Appears at night.
The Screamer is a zombie with no arms. When it sees you, it screams, summoning an army of zombies. Has high health.