Umbral Tide
From Warhammer - The Old World - Lexicanum
The Umbral Tide was a Black Ark of Naggaroth. [1a]
History
The ark was part of a raid on Lustria in 2512 IC but after the raiders are defeated by an army led by Kroq-Gar, the Umbral Tide itself is grounded by magic and destroyed in the Black Way. [1a]
Although the ships defence towers had at first took a heavy toll of their attackers, Salamander hunting packs emerged from the water to burn them and thier defenders allowing the Kroxigor and Skinks to board and slaughter all those on board. [1b]
The burnt and battered but still vast hull still remains, sticking out of the mudbanks. [1b]
Sources