Vulture Aid increases drops in a sense. Giving enemies the ability to drop small Aether canisters and ammo pick-ups. These are only visible to those with Vulture Aid.
Fetid Upgr-Aid: On death, zombies have a chance to create a gas cloud that charges your Field Upgrade.
Smell of Death: On death, zombies have a chance to create a gas cloud that conceals you while standing in it.
Parting Gift: Vulture Aid ammo drops give more ammo to Wonder Weapons.
All of these are going to be earned as part of the upcoming event. Apart from Holiday Cheer which can be earnt in Jingle Hells. Apparently hinted to also be added to the pool after the holiday season.
Power Keg: (Rare) - Spawns a Max Power power-up.
Time Out: (Ultra) - Last three minutes -Clear all Normal and Special enemies and end the Round. Normal spawning will not resume during this time.
Holiday Cheer: (Whimsical) - Zombies have festive decorations.
Light Mend instead transforms the effected zombie into a healing glyph that heals nearby injured allies. Also deals the new Light damage element. It is unlocked as part of Merry Mayhem.
Tesla Storm returns and pretty much functions (seemingly) the same as it does prior. It is unlocked as part of Merry Mayhem.