An old glintstone blade that has been stained with blood.Reduces FP consumption of sorceries and incantations at the cost of maximum HP.
The old sorcerers would slice open their hearts with these blades to imbue a primal glintstone with their soul, and thus did they die.
Acquisition
Obtained from a chest in the cellar of Stargazer's Ruins in central Mountaintops of the Giants. The cellar is locked by a seal, which can be dispelled by summoning the Spirit Jellyfish Ashes near the NPC jellyfish that speaks, near the center of the ruins. Note that the NPC jellyfish does respawn, if killed.
Notes
25% FP reduction is roughly equal to an extra 33.33% FP when casting spells. This will vary a bit depending on the cost, decreasing slightly if 75% of a spell's cost isn't a whole number since the cost is rounded up.
The 15% HP reduction is quite harsh, with 1900 HP (60 Vigor) being reduced to 1615 HP (roughly 46 Vigor), 1704 HP (50 Vigor) being reduced to 1448 HP (roughly 40 Vigor), and 1450 (40 Vigor) being reduced to 1232 HP (roughly 35 Vigor). Useful for low levels but since this items is only available quite late, it is best if you are quite mindful of the penalty.
The FP boost means effective Mind becomes greater at higher levels of Mind without it. 221 FP (38 Mind, maximum recover of Flask of Cerulean Tears at +12 with no bonuses elsewhere) becomes 294 FP (roughly 49 Mind), 173 FP (30 Mind) becomes 230 FP (roughly 39 Mind), 121 FP (20 Mind) becomes 161 FP (roughly 28 Mind).
Glintstone Scarab, a helm that provides a similar (15%) FP discount for sorceries at the cost of increasing damage taken. Both items can be equipped for a combined 36.25% discount on sorceries.
Incantation Scarab, a helm that provides a similar (15%) FP discount for incantations at the cost of increasing damage taken. Both items can be equipped for a combined 36.25% discount on incantations.