Even though Mikkel Borg Bjergsø wasn't the first person to brew an IPA with only one style of hops, he is possibly the one most responsible for, or at least famous for (among his many other beers) the "single hop" IPA. Warrior is one of ten varieties in his first Single Hop series that also included Amarillo, Cascade, Centennial, Chinook, East Kent Golding, Nelson Sauvin, Nugget, Simcoe, and Tomahawk. The series also included, or was followed by, Mikkeller 10, which was brewed with all 10 hops from the series.
The Warrior Single Hop starts with a thick, fluffy head with aromas of yeast, citrus, raisin bread, cinnamon, and a little earth. Flavors of sweet caramel, grapefruit and muscat are complimented nicely by earth and grass notes as well as a slight tartness. It's incredibly smooth and the carbonation is lively but not biting. Pretty bitter finish.
I've had the Nelson Sauvin Single Hop a few times before as well and what I like is that each of the beers are different, and that's exactly the point! Besides just being tasty, the Single Hop series is a great way to get familiar with the aromas and tastes associated with specific types of hops. Look for 5 more Single Hop IPA's from Mikkeller soon; Citra, Sorachi Ace, Summit, Apollo, and Bravo.