Blackrock prism

Small prisms frequently occur as a byproduct of large scale magical castings involving the mineral blackrock. Such prisms feature prominently in Ultima VII and in Ultima Underworld II.

History

Ultima VII

The massive blackrock constructs created by the Guardian contained miniature "echoes" of their geometric form within them and these objects could be used to achieve a variety of magical effects if removed. In Ultima VII such prisms existed within the Sphere, Tetrahedron and Cube Generators, which had been erected to assist in the Red Titan's invasion of Britannia. In the course of forestalling such an eventuality, the Avatar would have to obtain the prism from within each Generator's defenses in order to destroy them. One of these objects, a miniature blackrock cube, had the curious effect of coercing whomever stood in its presence to speak truthfully, which allowed the hero to glean much needed information about Fellowship operations. Eventually, all three prisms would have to be fitted into the pedestals of the Black Gate in order to pierce the barrier that surrounded it.

	Form of the Prism	Where to find it
	Tetrahedron	In the Tetrahedron Generator
	Sphere	In the Sphere Generator
	Cube	In the Cube Generator

Ultima Underworld II

Later, in the course of Ultima Underworld II, the Guardian would craft a massive blackrock dome over Castle Britannia, trapping all who had been feasting within. In journeying to dismantle this prison, the Avatar would discover a prismatic "echo" of the casting in bottom of the castle's sewer system, in the form of a blackrock jewel. Through this gem, the Avatar visited eight different worlds, retrieving an additional reverberant prism from each one. These eight gems (shaped like a small sphere, cube, diamond, large sphere, cylinder, tetrahedron, rectangular cuboid and heart, respectively) would be treated by the court magician, Nystul, before being reabsorbed by the larger jewel – a process that would slowly weaken the structure of the surrounding dome.

	Form of the Prism	Where to find it
	Small Sphere	Tarna, in the posession of Borne
	Cube	Basement of Killorn Keep, in the trap room
	Diamond	Anodunos, southwestern shore of the river on the lower level
	Big Sphere	Talorus, middle of the lava pit
	Cylinder	Scintillus Academy, on the big pentagram
	Triangular Prism	Pits of Carnage, in the possession of Dorstag
	Rectangular Cuboid	Rhiannon, cave-in near the blackrock wall
	Heart	Ethereal Void, in the Shrine of Spirituality

Lore

“

After that task has been completed, a smaller Tetrahedron will remain in place of the larger one. The Avatar will have great use for the smaller generator, and should take it. By solving the puzzle of the red and blue Moongates, the Avatar can obtain the smaller Sphere within. This, too, is an important key to solving the Avatar's quest, and should be kept like the small Tetrahedron. And once inside the generator, the Avatar must solve a puzzle, avoiding the dangerous fire traps designed to prevent access to the smaller Cube. After the small Cube is obtained, I will again speak, telling the Avatar to carry it to Buccaneer's Den. – from Key to the Black Gate (Ultima VII)

Trivia

• Should the Avatar try to leave without picking up a prism in Ultima VII, then the companions will call attention to it, suggesting Origin might have expected players to easily overlook them.
• The three generator shapes also appear in Ultima VIII, specifically inside Mythrans' house, as an object which morphs constantly between those shapes.

Gallery

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  Companions reminding the Avatar

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  The small cube demonstrating its coercive properties

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  The blackrock jewel