The Heart of the Guardian, a relic of considerable age, is a crystal that Suvam Tan, a Rodian inventor, unearthed on Yavin 4's surface. This discovery occurred sometime before the outbreak of the Jedi Civil War. Revan, after his redemption, might have used it as a lightsaber crystal, imbuing the weapon's blade with a distinctive bronze tint and a yellow center. This Heart was one of two fabled crystals that Revan may have acquired from Tan as he neared the conclusion of his mission to locate and obliterate the Star Forge, with the Mantle of the Force being the other.
When integrated into a lightsaber, it had a positive influence on the other crystals present, resulting in a swift and potent blade ideal for lightsaber combat.
It is speculated that the Heart played a role in the establishment of the Jedi Order. According to the Order's prophecies, the Heart would manifest during times of great upheaval, aiding in the salvation of the galaxy. Conversely, the Sith considered it a relic of their own heritage, believing it would facilitate their dominance over known space.
In Star Wars: Knights of the Old Republic, specifically the PC, mobile, and Nintendo Switch editions, this crystal is available for purchase at Yavin Station for a price of 20,000 credits; the Xbox version features Yavin as downloadable content. The bronze blade color is unique to this particular crystal within the game.
The crystal's effects are likely to fluctuate based on the other crystals used in the lightsaber. Furthermore, the benefits observed in the right hand will not be identical to those in the left. As an example, when wielded in the right hand, the Heart of the Guardian will nullify a VS Dark Side benefit crystal and substitute it with a Blaster Bolt Deflection benefit, but this Blaster Bolt Deflection benefit will not be present when used in the left hand.