When you enter Cragal Shrine, there's a scene with Zig. After the scene, get the treasure and head for the northeast corner of the shrine. (Ignore the door in the south; it won't open until the New Game+.)

There's another scene with Zig, but he disappears the moment he thinks there's someone else in the shrine.

Olivia performs her purification ritual, and then says she's ready to go on to the Shadow Shrine, which is south of your current location.

After you exit Cragal Shrine, though, Olivia remembers that the Shadow Shrine can't be reached on foot, and asks if you know where to get a ship? (So now, it's back to the Guild to ask for a ship. Good thing you've still got that Coupon...)

Map and treasure list by Searinox119

Treasure

• T1 - MP Seed x3
• T2 - Delete Fossil
• T3 - Economizer Jewel
• T4 - Midnight Knuckle +20 (VIT 26%, HP Regen 12%, Sleep 30%, Poison 18%)

Learnable Skills

Tenebrant City ~ Cragal Shrine

No.	Name	Skills
27	Blood Tri-Nuclei	HP Absorb, Poison Sphere
139	Hard-Back Turtle	Bite, Scramble Hit
181	Lizardman Warrior	Slash, Armor Break
227	Naughty Pixie	3-Shot, Random Shot, Eternal Song

In the New Game+ the restricted area is open, and it has 8 new treasures.

Restricted Area Treasure

• T1 - Razor Sword +12 (Paralysis 23% Sleep 26% Confusion 38% Virus 23%)
• T2 - Gold Jewel
• T3 - Floating Stick +42 (Fatigue 45% Rage 50% Idle 62% Confusion 50%)
• T4 - Beast Claw +20 (HP Regen 20% MP Regen 22% HP 22% MP 26%)
• T5 - Delete Fossil x5
• T6 - Four-Leaf Clover x2
• T7 - Ability Seed x3
• T8 - Rusty Scythe