The F.O.D. (fly of destiny) was first brought to my attention by the guys in the Pueblo, CO Drift fly shop years back. It's essentially a pheasant tail with a thread underbody and dubbed thorax. They said the trout were being super selective on the Ark tailwater and that this pattern (along with a few others) combined with 7x tippet was my best hope. Sure enough, those trout were being super selective. After a day of trying, and failing, I tyed one on. To this day...one of my largest trout ever. Enough said...except I still use it on tailwaters everywhere and with selective mayfly hatch feedings. Great name too, right? Available in multiple colors. Available in several options through out nymph section as well.