This pattern came from Grabflies "King Intruder Leech, Red" but I have only fished it for Winter Steelhead. In off color rivers like the Hoh river on the Olympic Peninsula. My first try with this fly I caught two Steelhead and no other flies were producing any results. I used a four inch King Intruder Leech, Pink on the Hoh, but clearer water rivers I use the three inch size.
Fly is tied using black cross cut rabbit strip tied on braid line like a Moal Leech, then lots of Rhea spun on, followed by Flashabou, and Guinea and a bead cone. The Black Rabbit core gives this fly lots of silhouette and animates the flashabou.
4 inch recommended for King Salmon, and Winter Steelhead
3 inch for Steelhead and clearer water conditions for Salmon
Size 2, 1, 1/0 trailing Intruder Hook