Part 1: the murder
Part 2: the Nightmare begins (get it? because they cast the spell nightm- oh why do I bother with you people)

The chicken saga has finally reached its climax, and unfortunately they didn't manage to kill the party before the story demanded their removal*, but they did manage to traumatise them slightly, so that's nice. When I started this campaign 28 sessions and 7 months ago, I did not expect 5 of those months and 3 levels of gameplay to have a chicken revenge subplot lurking in the background. Actual encounters usually had about 4 sessions between them, but they stayed on the players minds the whole time.

The lead up encounters went exactly as planned, though some extra downtime taken by the party meant they went through a lot more nightmares than expected - still, it was fun seeing where each of their dreams started, and what happened to twist it for each character. Having met the first chicken and day after day of waking up Fatigued, they were fully expecting another chicken.
What they didn't expect was for the second chicken to run through a wall, peck at their feet (2d6 void damage), then run through a different wall. They especially didn't expect that to happen in the middle of fighting a wood golem. And they did not enjoy trying to chase it down, eventually losing it in a tangle of small rooms (where it was destroyed by persistant damage).
The third chicken was easy enough for them to destroy, as it simply stood in place screaming endlessly as it summoned pillars of hellfire to burn the party with (2d6 fire damage, basic reflex save). While this was the shortest encounter at only 2 and a bit rounds, the image of it left a lasting impression on the characters and players. Stood stock still, flames billowing around it, burnt wings raised to the sky as it screamed defiance at their strikes. The PCs got off lightly, but the players were shaken.
When they encountered the fourth and final chicken, they were bemoaning their decision 5 months ago to disarm a trap with chickens as soon as they opened the door. It was hanging around with 4 corpselights and spent the entire fight showing the party visions of how it died (will save or 2d6 persistant mental damage). While the fight overall left them satisfied with how they'd grown in ability (2 corpselights had nearly killed them 3 levels earlier), the chicken left a bitter taste in their mouth. Not literally, they didn't eat the ghost chicken, they just felt bad about killing it again.

The party could feel the final showdown coming, and despite their attempt to delay (they refused to accept that the answer to a puzzle might be the power of love, so spent 2 and a half hours dicking around trying other solutions after someone first suggested it) had to face it eventually - and it came in the form of a gigachicken. The final chicken in the group, killed by a beam of kaiju, had grown to kaiju propertions (Huge size plus Impossible Stature), and alternated between showering the party with angry chicken ghosts (Telekinetic Assault reflavoured into a cuccoo storm for 2d6+4 bludgeoning damage) and smashing its beak down on party members within 15 feet (2d8+4 void). While this went on, the rest of the flock harrassed the party with more pecks, hellfire, visions of death, and a foggy haze from Brrkit and Hypokokoko's fire and water interacting to conceal everything on the battlefield.
Extensive healing had to be deployed in the fight to keep everyone up as the AOEs weathered away at them, and while the tank tanked admirably, he spent much of the fight on the edge of collapsing, even after dealing with the biggest threat. Unfortunately for the chickens, the party have become fairly proficient in working together and killing ghosts now, so while they eventually won, and the chickens ghosts were drained away by whatever evil lurks at the bottom of the dungeon, they did not get out unscathed.

Honestly, I am a little disappointed - had Skiaknorth not been hit by a pair of crits that rendered his resistance to physical damage moot I think I could have killed one of the PC's, maybe even 2 with bad luck on the death rolls. On the other hand, the chickens have made the players think a lot harder about the consequences of harming living beings, especially while in a giant spooky lighthouse that fires beams of ghosts, and they gave lots of praise for the whole experience so I guess that's a plus or something. I would have preffered to kill a pc

Anyway, elsewhere they left a Morlock Ghoul sat in a beam of necromantic energy and feating on the corpses of other ghouls, then went downstairs and turned the beam of necromantic energy off. I'm thinking of turning him into some kind of slighted undead wendigo thing to chase them down? Revenant maybe? Lemme know what you think.

Stats: Mini chickens used the same statblock as last time, with the weak template for the lead up fights, and the elite template for the showdown. Skiaknorth has the most changes, though nothing major:

Special Abilities: Most abilities come from the optional Ghost abilities (pre-remaster) - the +2 to damages is an effect of the Elite template:
Memento Mori:

The ghost causes one creature within 30 feet to relive the ghost's death. The target must succeed at a Will save or see and feel what the ghost did, taking 2d4 + 2 persistent mental damage. All other creatures are Concealed to the target until the persistent damage ends.

Pyre's Memory:

The ghost causes great gouts of flame to erupt without warning.The ghost picks three 5-foot squares within 30 feet. Creatures that start in or enter one of these squares take 2d6 + 2 fire damage, subject to a Basic Reflex save. The flames last for 1 minute and don't set other things alight unless the ghost wishes. If the ghost uses this ability again, it dismisses any existing flames.

Telekinetic Assault was renamed to GigaChicken Assault, but functions much the same:

The ghost cries out in pain and anguish as its flock flies about about attacking all enemies in a 30-foot emanation. Creatures in this area take 2d6 + 2 bludgeoning damage, subject to a Basic Reflex save.

Impossible Stature was taken from the Hekatonchiere to emphasise Skiaknorth's massive size:

30 feet. This titanic chicken warps perception and distance around them, seeming even larger and more imposing. A creature that enters or begins its turn within the emanation must succeed at a DC 23 Will save or its movement within the aura is movement over difficult terrain (greater difficult terrain on a critical failure) for 1 round.

*mostly. Every rule has exceptions, and the players did speculate on new forms. Chicken Hydra, anyone?