All 16 Onsen Egg Locations in Heartopia
The Onsen Egg Promise is a 16-day Winter Frost quest where you photograph one cracked egg per day across Onsen Mountain and Winter Utopia. Complete all 16 to permanently unlock the Onsen Egg cooking recipe — one of the best gold-per-minute methods in the game.
What Is the Onsen Egg Promise Quest?
The Onsen Egg Promise is a seasonal quest tied to the Winter Frost event, running approximately January 31 through February 14. Each day, a new cracked egg appears somewhere in the Onsen Mountain or Winter Utopia regions. Your task is to find it and take a photograph using your camera tool.
Unlike standard collectibles, these eggs unlock sequentially — you must photograph Day 1's egg before Day 2's egg appears. Missing a day does not skip an egg; it simply delays your progress. After photographing all 16 eggs, you permanently unlock the Onsen Egg Recipe.
16 Days
1 egg per day
Photo Quest
Use camera tool
Permanent Recipe
Keeps after event
260 Gold
Per 3-star egg
All 16 Egg Locations by Day
Eggs appear one per day in sequential order. Each egg is a cracked, glowing object — look near landmarks and structures. Use your camera to photograph it once found.
| Day | Area | Location Description |
|---|---|---|
| 1 | Onsen Mountain | Next to the welcome sign at the mountain entrance |
| 2 | Onsen Mountain | Behind the first hot spring pool near the wooden fence |
| 3 | Winter Utopia | Atop the moose statue at the ice-skating rink |
| 4 | Onsen Mountain | Under the wooden walkway near the Old Sea viewpoint |
| 5 | Winter Utopia | Beside the snowman cluster near the lodge entrance |
| 6 | Onsen Mountain | On a rock ledge above the second hot spring terrace |
| 7 | Onsen Mountain | Next to the bus stop bench at the mountain summit |
| 8 | Winter Utopia | Behind the frozen waterfall on the northern cliff path |
| 9 | Onsen Mountain | Inside the bamboo grove east of the main bath area |
| 10 | Winter Utopia | On top of the ski rental cabin roof (use ramp) |
| 11 | Onsen Mountain | Near the stone lantern along the upper hiking trail |
| 12 | Winter Utopia | Under the Christmas tree in the central plaza |
| 13 | Onsen Mountain | At the cooking booth alcove beside the boiling baskets |
| 14 | Winter Utopia | On the frozen lake edge near the ice fishing hole |
| 15 | Onsen Mountain | Hidden behind the towel rack at the outdoor bath entrance |
| 16 | Onsen Mountain | Final egg on the shrine platform at the mountain peak |
Tip: 10 eggs are on Onsen Mountain, 6 are in Winter Utopia. Plan your daily route accordingly.
How to Cook Onsen Eggs
After unlocking the recipe, head to the boiling baskets on Onsen Mountain (near the bus stop area). These special baskets only cook Onsen Eggs — they cannot be used for other recipes.
- Buy raw eggs from NPC Massimo in the market (stock up 20+ for efficiency).
- Travel to Onsen Mountain and locate the boiling baskets near the hot springs.
- Place eggs in any available basket — you can use multiple baskets simultaneously.
- Wait for the cooking timer to complete. Eggs cannot burn, so no monitoring needed.
- Collect finished Onsen Eggs and sell or gift them.
Pro tip: Use all available baskets at once. Since eggs cannot burn, you can start multiple batches and complete side tasks while they cook. This maximizes your gold per trip.
Onsen Egg Sell Prices by Quality
| Quality | Sell Price | Notes |
|---|---|---|
| ★☆☆ | 90 gold | Base quality, no bonuses |
| ★★☆ | 170 gold | Requires cooking skill level 3+ |
| ★★★ | 260 gold | Max quality — best profit per egg |
Worked Example: 16-Day Onsen Egg Completion Plan
Here is a day-by-day strategy to complete the quest efficiently while maximizing gold from cooking.
Days 1–5: Learn the Routine
Log in daily and head to the egg location listed above. Each photo takes under 2 minutes. Buy 10 raw eggs from Massimo on Day 1 to have stock ready once you unlock the recipe.
Days 6–10: Build Egg Stock
Continue daily photos. Buy another 20 raw eggs from Massimo. You now have 30 eggs ready for batch cooking. Focus on upgrading your cooking skill to level 3+ for 2-star and 3-star output.
Days 11–15: Almost There
Keep photographing. If you have cooking skill 3+, start practicing other recipes to improve quality odds. Buy another 20 raw eggs (total stock: 50).
Day 16: Recipe Unlocked!
Photograph the final egg at the shrine platform. The Onsen Egg Recipe unlocks immediately. Head to the boiling baskets and cook all 50 eggs. At 3-star quality, that is 50 × 260 = 13,000 gold in one session.
Daily Routine Tips for Onsen Egg Farming
- Check the day number first. Open this guide, find today's day number, and go directly to that location. No searching needed.
- Combine with daily commissions. If your daily tasks include Onsen Mountain quests, do the egg photo first since it takes under 2 minutes.
- Stock raw eggs early. Massimo sometimes has limited daily stock. Buy eggs on days you visit the market for other supplies.
- Use all baskets when cooking. Multiple baskets cook simultaneously, and eggs cannot burn. This is the single biggest time-saver for gold farming.
- Do not skip days. Missing a day does not skip an egg — it delays your progress by one day. Consistency is more valuable than speed.
Frequently Asked Questions
How do I start the Onsen Egg Promise quest in Heartopia?
The Onsen Egg Promise quest activates automatically during the Winter Frost event (approximately January 31 to February 14). Visit Onsen Mountain after the event starts and look for the first cracked egg near the welcome sign.
Do I have to find all 16 eggs in order?
Yes. Only one new egg appears each day, unlocking sequentially from Day 1 through Day 16. You cannot skip ahead or find future eggs early.
What happens after I photograph all 16 Onsen Eggs?
Completing all 16 photographs unlocks the Onsen Egg Recipe permanently. You can then cook Onsen Eggs anytime using the boiling baskets on Onsen Mountain.
Where do I buy eggs for cooking?
Purchase raw eggs from NPC Massimo in the market area. Each egg costs a small amount of gold. Stock up before heading to the hot springs to cook in bulk.
Can Onsen Eggs burn while cooking?
No. Unlike regular cooking, Onsen Eggs cooked in hot spring baskets cannot burn. You can safely use multiple baskets simultaneously for batch cooking.
How much are 3-star Onsen Eggs worth?
Three-star Onsen Eggs sell for approximately 260 gold each. With batch cooking across multiple baskets, this becomes one of the most efficient gold-per-minute recipes in the game.
Can I cook Onsen Eggs after the Winter Frost event ends?
Yes. Once you unlock the recipe by photographing all 16 eggs, you keep it permanently. The boiling baskets on Onsen Mountain remain available year-round.
Related Guides
- Snow Concert Event Guide — another Winter Frost seasonal event with exclusive rewards.
- Wild Animals Guide — find all 8 wild species and their favorite foods across every region.
- Animal Favorite Foods — maximize farm animal friendship for better products and gold.
- Aurora Banquet Event Guide — seasonal cooking event with limited-time recipes.