STREAM HEARTSSTREAM HEARTS / GAME GUIDE
Card and upgrade probabilities
Card selection and mine upgrade rules for Stream Hearts 1.0.4. Star Shards and game coins are in-game resources earned through gameplay.
Roll the Ball · Rumbling Expedition
Card rarity rates by luck level
On a small screen, scroll sideways to see the full table.
| Luck level | Common | Rare | Epic | Legendary |
|---|---|---|---|---|
| 0 | 55% | 34% | 9% | 2% |
| 1 | 49% | 35.8% | 12% | 3.2% |
| 2 | 43% | 37.6% | 15% | 4.4% |
| 3 | 37% | 39.4% | 18% | 5.6% |
| 4 | 31% | 41.2% | 21% | 6.8% |
| 5 | 25% | 43% | 24% | 8% |
Each luck level changes Common by −6 percentage points, Rare by +1.8, Epic by +3 and Legendary by +1.2. Applied luck levels range from 0 to 5.
Draw candidates, then choose one card
- The standard selection offers 3 candidates; the 10-draw selection offers 10. You choose one card from either set.
- Card abilities and rarities are drawn separately. Each currently eligible ability has an equal chance. An ability is not repeated within a candidate set until the eligible pool is exhausted; drawing then resumes from the full pool.
- If none of the first 9 candidates in a 10-draw selection is Epic or Legendary, the 10th is set to Epic. If any of the first 9 is Epic or Legendary, the 10th also uses the rarity rates in the table.
- The Epic guarantee applies to the candidate set. The rarity of the one card you receive depends on the candidate you choose.
Star Shard Mine · pickaxe and fan-slot upgrades
Before upgrading, check the rates for the current level in the pickaxe or fan-slot upgrade controls.
Probability values shown in the controls
- Success
- Failure
- Unchanged
- Downgrade
- Destruction
Rates are displayed as percentages with up to two decimal places. The same screen shows the success-rate adjustment from accumulated failures that leave the upgrade level unchanged.
Standard upgrade conditions
Downgrades can occur from a current upgrade level of +5, and destruction from +10. Use the values displayed immediately before your attempt.
Catch-up adjustment for equipment
When equipment behind a teammate’s meets the catch-up condition, the controls show a 95% success rate and protection against downgrade and destruction. Check the upgrade screen to see whether the adjustment applies.
The mine’s dedicated OBS game output does not show the probability card. Check the streamer’s control screen for rates and active adjustments.