In this guide, you will come to know how to get Omega Isotopes in Warframe. Go through the guide and follow the simple instructions to get it.
Omega isotopes can only drop from whatever planet the Balor Fomorian is near/on when the Fomorian threat Event is active.
When the Fomorian event appears, you will need to check the events tab to see which planet the Balor Fomorian is on/near. And then you have to run the missions on that planet, and the enemies you kill will have a chance to drop omega isotopes.
You can run the exterminate missions since they don’t take very long, and they have a good amount of enemies to kill. So you will have a pretty good chance at getting omega isotopes, but you can run whatever mission type you want, just as long as it’s on the planet that the Fomorian is on.