Adventure Racing is all about speed and efficiency. On the one hand, the boat has to be light enough to not slow you down when you are carrying it on overland stages. On the other hand, any extra speed that you can maintain on the water is critical. The first generation Gnu (introduced in 2012) and the longer second generation Gnu (introduced in 2017) were extremely light for a full two person packraft, but the kneeling position was challenging for extended paddling stages especially when following long stages of running or biking.
Enter the 2019 Gnu, which features the same hull shape as the Oryx canoe but utilizes a long, inflated center seat to provide a keel and allow both paddlers to sit with their legs extended and feet below the hips. This is the optimal position for maintaining power and efficiency over long distances with a kayak paddle. The higher volume hull also produces less draft, which further increases paddling efficiency. The top speed of the Gnu is not noticeably faster than the prior versions, but it is much easier to maintain over distance which can dramatically reduce stage times.
While the Gnu is optimized for most adventure racing courses, the Forager is a better option for courses that are mostly whitewater and the Explorer 42 is a better option for courses with very short paddling sections that require you to carry your boats for long distances.