The Plaguebringer set is a vanity set consisting of the Plaguebringer's Skull, the Plaguebringer's Cloak, and the Plaguebringer's Treads. It is one of the six sets that were added as part of the Journey's End Vanity Contest; the original concept was submitted by SodaHunter.
The tooltip for the helmet is a reference to the multiplayer first-person shooter video game Destiny 2, as Ahamkara are a form of dragon in the game. It is also worth noting that an NPC from the game, the Drifter, often says "Trust!" at the end of sentences.