Mountain Sanctum is the clear pick, holding 28 of the 50 marked spots on the Operation: Egg Heist map, twice what Ancient Altar offers at 14. Dock Lighthouse Ruins accounts for 7, and Shipwreck Bay just 1, so the top two areas cover most of what you can find. A Legendary Chest is a map landmark type, and gathering the densest cluster in one run means fewer moves between drops. Start where the count is highest and work down from there.
Areas with Legendary Chest
| Area | Level | On the map |
|---|---|---|
| Mountain Sanctum | — | 28 |
| Ancient Altar | — | 14 |
| Dock Lighthouse Ruins | — | 7 |
| Shipwreck Bay | — | 1 |
Ancient Altar makes the sensible fallback when Mountain Sanctum is crowded or contested, and it pairs well with a landmark sweep. Wherever you settle, the walk is short once you drop in, so pick your stop by what sits alongside the chests. Nearly all of the marked spots keep a Luxurious Ruin Chest in view, and just over half sit within sight of an Exquisite Relic Chest, so you rarely leave with only the one find. The Ornate Stone Sarcophagus turns up beside a smaller share, worth noting if you spot one.
Open the Aniimo interactive map to see it with every other filter, or pick another from the list.