The boat you sailed in on is docked at Kaer Trolde Harbor, a place you should know well. Fast-travel to the “Marlin Coast” signpost and rest until night. If you try this during the day, you’ll be shot at by sailors, which doesn’t do much damage, but it can make it difficult for you to surface for air, or to board the ship. When it’s night, swim north-east to find the Emperor’s fleet, where your goal is to avoid the spotlights (if you’re spotted, just dive until they call off the search) and find the Emperor’s ship in the search area. When you approach the anchor of the correct ship, a stand-down order will be given. Swim up to and activate the anchor to climb aboard and have a quick - but productive - chat with Emhyr. Afterwards you’ll be back in Kaer Trolde Harbor and the quest “Veni Vidi Vigo” will end.

Veni Vidi Vigo (Level 28)¶

Next up you’ll need to talk to Crach to find out where Ermion is, who might be able to direct you to the Sunstone… but before you mess with that, there are a few more map markers to clear, after which it’ll be a straight shot to the end of the game. Might as well get these last few distractions done now that the main quest has taken you back to Skellige, and you’re between quests.

Guarded Treasure (Level 32)¶

Fast-travel back to the “Bay of Winds” signpost on An Skellige (the north-eastern most of Skellige’s islands) and commandeer a ship. Sail from the Bay of Winds to the north-west to find a crudely hatchet-shaped island north of a smaller island with a Hidden Treasure event on it. Sail to the bay on the western end of the island to find a beach you can use to reach the island, on which is a Guarded Treasure event. The guardian that gives this map marker its name is a Basilisk (level thirty-two), and since you recently slaughtered a beast of similar potency back in Velen, you shouldn’t need any advice as to how to take this one down. Kill the beast and loot a body in a shelter to the south to find the sword “Daystar” , then head up some stairs to the north-east to find a campsite, where you’ll find a chest to loot. Do so and complete this event.

Hidden Treasure (Level 48)¶

South and slightly west of where you are now is a large island off the coast of Ard Skellig (north of the Ancient Crypt signpost on the northern shore of Ard Skellig) with another event on it. Unfortunately, there’s also a very powerful creature here - an Archgriffin (level forty-eight). That’s not a typo, it’s by and far the strongest creature in the game, and without a bunch of otherwise-pointless grinding, you’re never going to be a match for it in a straight fight. You can, however, attempt to kill it by shooting it out of the sky as it flies around over the sea, letting the water do in a creature that is very hard to kill conventionally. Of course, your only reward for this feat is a chest containing some goodies - not bad, but nothing that really warrants so much work. Complete this event or skip it, as you will.

Treasure Hunt: Hidden in the Depths (Level 31)¶

Whether you kill the Archgriffin or avoid it, sail south to the Ancient Crypt signpost on the northern end of Ard Skellig. You’ll be coming back here shortly, but for now, fast-travel to the Harviken signpost on Faroe (the south-eastern island) and make your way to the south-western end of the island to find a Hidden Treasure event. Along the beach you’ll find a cave, near which is an Endrega Warrior (level nine) guarding a corpse. Squash the bug and loot the corpse to find a “Message” and a “Scratched Key” . Read the letter to start the quest “Hidden in the Depths” , then enter the cave and swim to the north-east, then dive and swim east to reach a cavern. In this cave beyond the water you’ll find four Endrega Drones (level twenty) and a Venomous Arachas (level thirty-one). Drink some Golden Oriole, apply some Insectoid Oil to your Silver Sword and use Igni liberally and you should be able to simply over-power your foes. When the bugs are dead, search the north-eastern end of the cavern to find a chest - the object of this event.

That’s all for exploration, now it’s time to hunt down Ermion, then obtain this Sunstone.