Heyo, thought this would help some peeps.

Chaingun: Primary fire
Fires a stream of bullets with moderate spread for several seconds.

Missile: Alternate fire
Wind up followed by firing 3 missiles simultaneously with moderate spread. Short cooldown.

Mortar attack: Reload key
Wind up followed by firing a cluster of missiles into the air that will target where players were when they were fired. This attack needs to be started while relatively close to survivors; if there are no survivors in range no missiles will be fired when the wind up is complete.

Invisibility: Flashlight key
Become cloaked; toggleable. Attacking will bring you out of stealth.

Tentacle Grab: Grenade key
The tentacle claw in your chest shoots out and snatches a survivor, bringing them to you. This attack must be used when near survivors; it will not even do the animation if none are nearby. Can miss if survivors move out of range after beginning the attack. Last time I checked, this wont actually break stealth and survivors can be snatched while invisible.

Healing syringe: Self-Heal key
Heal yourself a for a considerable amount of health derrr.

Melee: Melee bash key
This is context senstive.
While sprinting=Shoulder bash. Unparryable & hits multiple survivors in an AoE if it connects.
While moving left=Swipe forward and to the left of you.
While moving right=Swipe forward and to the right of you.
While moving forward=Do a Sparta-kick in front of you.
While moving backwards=Do a 360 degree spin that can hit multiple times. This attack is unparryable and seems to deal major damage against survivors who have been tentacle grabbed to you. This is the most lethal melee attack

Aiming down sights will do a roar.

Lemme know if i missed anything

I've only tested this against ai dummies and completely forgot about armor and perks getting extra health lol; forget what I said about the spinning melee being able to oneshot