In Season 3, players will need to acquire the Spark of Dreams profession crafting material in order to upgrade their crafted items to higher items levels. However, in order to combine 2x Splintered Spark of Dreams into a Spark of Dreams in Patch 10.2, players will expend 250x Flightstones as well.
Early datamining suggests that it initially costed 30x Drake’s Dreaming Crests, but Flightstones should be a better option that doesn’t require the exchanging of crests or specific content.