A semi mobile fortress placed in the mouths of rivers, bays, and other bodies of water up to several miles off shore
"Deepbend, the toughest place to live south of the wastes. The inmates are tough, so we gotta be tougher. They may complain of 'abuse' and 'cruel and unusual punishment' but you know, they deserve every last kick"
-Darner Gearbend, Warden.
The Rock of Gibraltar, once a stalwart of British power, the gate to the Mediterranean, now is a fortress for the Eurasian Alliance. It's fair teeming with neo-Soviets and submarines.
"Ye thought the orbital penitentiary around Venus was hard ta endure? That place is a vacation spot compared to Davy's Lockdown! If the guard borgs can't find an excuse ta peel the skin off yer bones and the inmates don't use ya for their bettin pool, the pressures o' bein that far beneath the waves will drive ya to the brink, mark my words!"
An underwater prison with a dark past, suitable for any sci-fi, neo-dystopian, or cyber punk setting.
It is said in the hidden myths of the banned and hunted Cult of Ma-O, that the Seamus Straits are where Ma-O fell when the god Jove hurled him from heaven. His physical body was smashed into pieces of amethyst and his spirit trapped within the warm waters. Here under the waves, once when built on dry land the pride and joy of the De Madden Company, Castle Seamus is now occupied by a unique underwater tribe.
The hammer of a war-god avatar, this massive weapon must be wielded by a giant or other supernaturally strong being. When struck against the ground, a massive seismic wave will propagate outward from the wielder subjecting all in its wake to a massive earthquake. This quake is strong enough to shatter castle walls.