The Maelstrom Crystal is a dark crystal that carries a high concentration of powerful Maelstrom energies.
The Maelstrom Crystal was created by XERRD from samples of solidified Maelstrom energies from the ruined Nexus Temple on Crux Prime, where the Maelstrom is at its strongest in the LEGO Universe. Since XERRD was planning on conducting their operations on LEGO Planet, far from the reaches of the Maelstrom, they created this crystal so that the organization would have an ample amount of Maelstrom energy to study. XERRD brought the Maelstrom Crystal to the LEGO Planet aboard their spaceship, the New Age.
XERRD brought the Maelstrom Crystal to a Temple of Creation on Adventurers' Island, hoping that the Imagination in the temple would prevent the crystal from acting volatile while they studied it. However, the crystal's Maelstrom energies reacted violently with the Imagination, creating a miniature Maelstrom vortex that corrupted the Temple of Creation into a Maelstrom Temple. Recognizing that it was too dangerous to handle directly, XERRD was forced to lock up the crystal deep in an Egyptian pyramid on the same island. There, the crystal was protected by various booby traps and an apocalyptic mural to keep trespassers away.
Through the vortex in the Maelstrom Temple, Baron Typhonus knew that the Maelstrom Crystal contained enough energy to allow him to quickly destroy the LEGO Planet and spread the Maelstrom's influence. He led Lord Sam Sinister to the crystal and tasked him with bringing it to the temple, believing that the Lord von Barron would be greedy and foolish enough to give him the Maelstrom Crystal.
The Maelstrom Crystal was retrieved by Sinister's team, including Greybeard and Frozeen. While Sam Sinister assisted Dino Attack Team's assault on the XERRD Fortress, Greybeard and Frozeen used the Maelstrom Crystal to navigate the Adventurers' Island jungle in search of the Maelstrom Temple. Along the way, they were constantly harassed by Mutant Dinos drawn to the crystal's power. They even encountered Zachary Virchaus, who knew the crystal's true purpose and let them take it away so that the Mutant Dinos and Stromlings would hunt them down.
At Dino Attack Team's camp, Frozeen and Greybeard met up with Sam Sinister again and continued their search for the Maelstrom Temple. Sinister discovered that, when he held the Maelstrom Crystal, the Mutant Dinos stopped attacking them, allowing them to travel to the temple without any further opposition. There, Baron Typhonus revealed himself and told Sinister to hand over the crystal. Fortunately, Typhonus's plans backfired, since Lord Sinister had finally learned to recognize traps, rejected Typhonus's false offers of power. During the battle for the Maelstrom Temple, Dino Attack Team passed around the crystal, preventing it from falling into the hands of Typhonus or his Stromling Explorers.
Ultimately, Sam Sinister took the Maelstrom Crystal again and was airlifted out of the Maelstrom Temple by a T-1 Typhoon. He was flown to a volcano, where he destroyed the crystal by dropping it into the lava below.
Because it was created from the crystallized Maelstrom energies at the Nexus Temple, the Maelstrom Crystal contained such a high concentration of Maelstrom that it could quickly destroy the entire LEGO Planet. However, these highly-destructive energies in a small volume also made the crystal inherently unstable, and melting the crystal in lava caused the newly-released chaotic Maelstrom energy to turn against itself and collapse. Like other sources of Maelstrom, the crystal can influence negative emotions such as greed, and it was thought to be the source of Greybeard's nightmares while he carried it.
The Maelstrom Crystal was surrounded by a purple mist that drifted in the direction of the Maelstrom Temple. Therefore, one could find the temple by following the crystal's mist like a compass. However, since Typhonus's plans depended on the Lord von Barron bringing him the crystal, only Lord Sam Sinister could hold the Maelstrom Crystal without being attacked by all Maelstrom-infected beings, including Mutant Dinos, within an indeterminable radius. Stromlings with independent thought, such as Zachary Virchaus, could resist the urge to pursue the crystal.
- Maelstrom Crystals are part of LEGO canon and are seen in LEGO Universe, including one carried by Nuckal that even matches the Dino Attack RPG crystal's physical description of resembling a purple Brickonium crystal. However, the specific Maelstrom Crystal seen in Dino Attack RPG is an independent creation by PeabodySam and is not based upon these canon Maelstrom Crystals, with any semblance between the two concepts being merely coincidence. Instead, it was largely inspired by the One Ring from The Lord of the Rings.
- In the early Dino Attack RPG, Jecht "Landro" Raptor told Sereve that "the jewel of Sentarie 9" was tied to the source of the Mutant Dinos. In current canon, this has been retconned so that Landro was talking about the Maelstrom Crystal.