WTB
Sendero TCS 650B x 47mm Gravel Tire

Best grip I have found (and I have tried many, many). Truly inspire confidence in technical stuff. They roll fine getting to the trail.

Only negative� The center tread on the back wears very fast as compared to the rest of the tire. Once this happens, they slip out on the steep loose stuff. But I love them so much I just view it as a cost for their wonderful grip elsewhere and buy a new one.

Gave them 4 stars just because they're a very niche tire, not something I'd roll all the time. That said, they've been my go-to gravel tire all winter. Plenty of traction on snowy, muddy, looser conditions. My experience with WTB tires in general has been great. Maybe a little difficult to set up, but once on the rim I really liked them (I've run Horizon in the past and currently keep a set of Byway's mounted during summer). The Sendero isn't something I'd run all the time, like I said above, but when traction is the goal, this one provides plenty. Considering their intended use, I wouldn't grade them down for rolling resistance as they are most likely to be plowing through snow or mud or other terrain that provides far more resistance than the tire/tread. If that's a concern for you, I'd probably look at something more like the Raddler/Riddler.

These are great tires for expanding your gravel machines capabilities on more technical terrain. They roll just fine on the road but expect the rear to wear pretty fast. To me, grippy tires are like health insurance. If you’re going to ride challenging terrain, do what you can to make it more enjoyable. These tires are smile generators when on steeper trails.

I bought this tires because I needed more grips after a nasty downhill fall on another set of tires. This tires are very grippy and also usable on the pavement. One downside for some people is that they are a bit noisy on pavement with the "swoosh" sound.