Garra Typhlops

Passage of Oaths, one chamber of the Cultist Lair, is where Garra Typhlops lives. A Legendary, it takes Seaweed (which the wiki ranks as an Unusual bait) in daylight, under Foggy weather, and only in Autumn. The game quote calls it a blind cave barb clinging to rocks in Iranian subterranean streams.

It earns 1200 base XP, 70th among 103 Legendary fish. Borealis Snapper and Floppy share that exact figure, Scalding Swordfish follows at 1100 and Brine Phantom at 1000. The Legendary tier is wide, and this one lands in its lower half, not at the peak.

The cave kinship is the interesting detail. Garra Andruzzii, the Rare from the Hall of Whispers, is a cousin in name and habitat, and its Spring season, 180 XP and Rare label make this Autumn Legendary about 6.7 times richer in XP on paper. The catch lines are shouted in capitals: "A GARRA TYPLOPS!", "CLINGS TO DARKNESS!" and "ETERNAL BLIND!" Weight and price are not listed, so the experience figure is the only number to work with.