Ruddy Sporeglider

Head to the Peculiar Cauldron in the Harandar zone at 40.7, 28.1. You will need 150 Crystalized Resin Fragments to unlock it.

Search the river between the northern waterfall shelf and the final shelf just before the Den for Flame-Hardened Sap objects — these are small treasures not visible on the minimap that glow with a faint shine. Key spawn locations run from at 40.35, 25.99 and 39.5, 23.72 in the north down through 41.45, 29.13, 41.08, 28.7, 43.1, 33.57, 42.33, 35.03, 41.95, 37.18, 41.64, 36.78, 41.89, 37.63, and 43.38, 41.95 in the south — these objects do not spawn in any other river, in the Den waters, or further east.

Each Flame-Hardened Sap object yields between 2 and 7 Crystalized Resin Fragments, and the objects hyperspawn so there will never be zero available — the faster you loot them, the faster they respawn. Once you have 150 fragments, return to the Peculiar Cauldron at 40.7, 28.1 to claim the Ruddy Sporeglider.