A practical order
Take the first shard to the three pillars in the Calico Desert and stand on the center tile while holding it. That spends the shard on the Galaxy Sword. Later copies can be bought from Marlon for 50,000g, so the pillar is a one-time door.
The full rate table is on the Prismatic Shard page. The rows below are the ones that change how you spend a day. Haley hates the shard as a gift. Everyone else loves it.
| Stop | Why | Chance |
|---|---|---|
| Mystic Stones | Best single rock. Mines floor 100+, Skull Cavern, Quarry, Volcano. | 25%, plus 1–3 iridium ore and 1–4 gold ore |
| Iridium Nodes | Common in deep Skull Cavern. 1.6 set this at 3.5%, down from 4%. | 3.5% |
| Skull Cavern treasure rooms | Worth opening every time. | 1 in 26 |
| Volcano summit chest | Once, the first visit to the top. | One shard |
| Omni Geodes | Crack them, but the shard is locked out until 15 have been opened. | 1 in 250 after that |
| Serpents on the way down | They are already in the way. | 0.1% |
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