Privateer Press has launched Longest Night: The Witchfire Ascendant.
From their website:
The Longest Night is a widely celebrated holiday in the Iron Kingdoms consisting of festivals and revelries with people celebrating by dressing up like the dead, drinking, and lighting off fireworks amid loud music and dancing. It is celebrated every three years at the end of the year as an extra day added to the calendar, therefore taking place after the old year and just before the new one. While the festivals are eagerly anticipated, Longest Night has an increasingly ominous reputation.
Many believe this day and night to be a time of black magic and misfortune. Some say the barriers between Caen and Urcaen—the realms of the living and the dead—become thin on this day and that the spirits of the restless dead manifest to haunt and torment the living. There are some who prefer to hide in their homes and bolt their doors rather than join the masked revelers cavorting in the streets.
The close of 608 AR brings another Longest Night. Amid warfare and turmoil the sense of dread and uncertainty is palpable, stronger than ever. Cryx has been on the rise, and graveyards have become fertile recruiting grounds for necromancers. The last few Longest Nights have been marked by tragedy. Between 605 and 606 AR, after the bloody invasion and occupation of Llael by Khador, the Balebrand of Cryx was made manifest. All those infected by the blighted harvest suffered from horrible dreams and waking delusions, turning violently on their friends amid the festivities. Just three years earlier, between 602 and 603 AR, thralls pouring into the city from the Widower’s Wood interrupted the festival in Corvis, killing anyone in their path as they battled their way to the Cathedral of Morrow. The terror of this invasion was amplified since so many of the city’s citizens had dressed as the dead, making for much confusion and misdirected violence. Memories of these incidents have many people fearful of the upcoming Longest Night, but many more are still eager for its festivals. There is no telling what things may go bump in the night as the sun sets for the last time on 608 AR.