The "cooldown" that you're referring to does exist, just not in the way you think. It doesn't shut down the drop chance completely (nor did it ever), it just diminishes your chances of pulling an exotic in comparison to the chance that you'd have if you waited a bit. [spoiler]For the sake of the example, I'm going to use numbers that are in no way, shape, or form the ACTUAL values that the coins give.[/spoiler] Say you've just started playing for the day and you pop a coin. That coin gives you a 10% chance to pull an exotic from the next Ultra kill. The Ultra dies, and you find an exotic engram. Now the cooldown begins. If you wait for however long (roughly 10 minutes) and then use another, you'll get the full 10%. If you don't wait, that chance is only 5%, or maybe (probably) less than that. The coins will still work, but not as efficiently as they would if you wait. Ultimately, the way these farms work is to increase the amount of rolls you get with the 3oC. You're burning through more consumables to produce the same net result in a shorter period of time, which is great if you've got the coins (both 3 of and strange) to burn. If you're on a budget, though, waiting for the higher drop chance would be better. Through the method displayed in the video, you'll probably get an exotic in every 10-15 3oC used (on average), but you'll get through those in a very short period of time. If you wait, the drop chance increases to one exotic every 4-7 uses (again, on average). Still, nice farm, though. I like using the Regicide mission as well (kill the ogre, let the cabal kill you, repeat) and others like using the Black Heart (or whatever it's called) from the Vanilla game. Your's doesn't consume that much ammo, though. I'll have to give it a shot.