Direct sources
Via relics
We assume ~2.5 min per relic opening (short fissure). Per-mission timings are labeled by source: derived from game mechanics or community-estimated.
Expected runs = 100/chance · Runs for confidence p = ⌈ln(1−p)/ln(1−chance)⌉ · In a squad of 4 opening the same relic, the chance your part shows among the reveals is 1−(1−chance)⁴.
Roadmap: get this part now
Every relic that contains it, how refining improves the chance, and which fissures are active right now to crack it.
Refining the relic with Void Traces raises the chance of rare drops (and lowers common ones).
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Refining the relic with Void Traces raises the chance of rare drops (and lowers common ones).
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Refining the relic with Void Traces raises the chance of rare drops (and lowers common ones).
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Refining the relic with Void Traces raises the chance of rare drops (and lowers common ones).
…
Live fissures from the Warframe WorldState. Chances from DE’s official drop tables.
Each run has a 4.43% chance. The curve is 1−(1−p)ⁿ: there is never a guarantee, only growing confidence.