Obtainable via the new ongoing event. Here's a guide courtesy of Beomi:
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Summer Festival today (Maris)
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First Time of this Event
Start: London 2 NPCs in front of Church
Follow the order
1) Oslo: choose one of 3 trade goods and deliver 200
Barley (Copenhagen) /
Wheat (Lubeck, Seville, Nantes) /
Wild Oats (Oslo)
NPC: Fest-loving Resident (Church, not in map) => Jenny (Mansion) Finished
2) Stockholm: conversation with NPC
NPC: Miles (Mansion, not in map) => Stina (near Port-Square, not in map) => Miles (Mansion) => Flower Crown Maker (Craft Shop) => Miles (Mansion) Finished
3) Copenhagen: Speak to Enthusiastic Resident just north of Town official
Deliver all 3 trade goods to Craftsman at Work (marked on map by Craftsman):
Coal (Danzig / Hamburg) X 50
Lumber (Danzig / Bergen / Oslo) X 20
Rocks (collect at British Isles South Coast, recommended; disable Trade Goods Auto-Dumping if it is active!!) X 10
NPC: Enthusiastic Resident (Left side of Town Official, not in map) => Craftsman at Work (Craft Shop) Receive Anchor and Finished
You receive
Summer Ticket x1 and
Summer Gift Ticket x1 for each city quest completed. Finally, go to London and talk to the Solstice Fest Assistant for the initial completion rewards.
Male toon: Male Banador / Female Toon: Female Banador, you can take as the reward.
2nd Day onward (can complete in any order):
Oslo: 200 Wheat or Barley or Wild Oats to Jenny
Stockholm: Deliver 5
Red Flowers and 5
White Flowers to Flower Crown Maker
Copenhagen: Deliver 20 Lumber, 10 Rocks and 50 Coal to Craftsman at Work
Rewards:
Sweet Treat Basket x5 (from each city NPC)
Speak to the Solstice Assistant in London afterward for:
Shiva's Arrow &
Thor's Thunder, x1 each
Special rewards on 5th consecutive and 10th day only:
Midsummer Ticket x1