Isos: Drop sources, locations, and probabilities

Tips

There are many ways to get Isos in Warframe, but my recommendation for optimal efficiency would be to try one of these missions (in this order):

• Veil Proxima/Calabash : It's a Skirmish Extra mission (level 45-49). Probability to get it: 14.29%.
• Veil Proxima/Numina : It's a Skirmish Extra mission (level 48-52). Probability to get it: 14.29%.
• Veil Proxima/Arc Silver : It's a Skirmish Extra mission (level 51-55). Probability to get it: 14.29%.
• Veil Proxima/Erato : It's a Skirmish Extra mission (level 54-58). Probability to get it: 14.29%.
• Veil Proxima/Lu-Yan : It's a Skirmish Extra mission (level 55-59). Probability to get it: 14.29%.

These recommendations are based on the usual missions lengths, and the probability of getting the resource dropped.
Only mission rewards are listed here. Enemy drops are not taken into consideration, there might be more efficient options available in some cases.

Missions with a Chance to Get Isos as a Reward

Mobs Dropping Isos

This is a region resource that can also be dropped by most ennemies on the corresponding planet(s). But here are a few other sources.

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