Euro style nymph fishing isn't always about tiny flies, fragile tippet, and gross numbers of trout. If you want to hunt for big fish that feast on minnows and crawfish near the bottom, these flies are for you. While they can be fished a variety of ways, savvy anglers love tight lining these flies and actively moving them along the bottom. Some of the biggest fish in the river can only be caught this way. Think about it.