Shoe Review: Merrell MTL Skyfire 2 ($200)

By Brian Metzler

A lot of people have asked me lately if I think trail running will continue to boom and my answer is always: “Yes, absolutely!” But the post-pandemic awakening that has seen more runners hitting the trails won’t be only about ultrarunning, but instead I believe the biggest growth segment will be in distances much shorter than a marathon. Ultrarunning is great for many reasons, but, c’mon, how many people realistically want to run 50 or 100 or 200 miles? Probably a relatively slim number of the total running population, right? But just about every runner would love running a 5K, 10K or half marathon on trails. Because what’s not to love? Running (relatively) fast, feeling the wind in your face, great scenery, cool race course features and a satisfying athletic output without totally depleting and destroying yourself.

What’s my point? Following Hoka’s lead, there’s been a huge influx in maximally-cushioned trail running shoes in recent years. Those shoes are cushy and stable, capable of providing long-haul comfort for your feet and legs for very long runs. But as short-and-fast trail racing begins to rise, there are also a lot of sleeker, faster and more agile shoes coming out. One of the best new ones is the Merrell MTL Skyfire 2, which blends a modestly thick layer of responsive midsole foam with a low-to-the-ground geometry that provides exceptional feel for the trail. It’s not only a good example of a shoe that offers the best of both worlds – light and nimble, but cushy and comfortable – but it’s exactly the tool needed for running fast over short to moderate trail races, routes and ridgelines.

What’s New: Although there was an original MTL Skyfire model that debuted in 2020, the new version is much more than an updated model. The MTL Skyfire 2 is a top-of-the-line lightweight race car for the trails. Key components include a two-part, dual-density FloatPro Foam midsole sandwiched around a flexible plastic protection and stability plate, a thin web-like Vibram MegaGrip rubber outsole and a durable, rip-stop engineered mesh upper with subtle TPU reinforcements.

Fit/Feel/Ride: The MTL Skyfire 2 fits true to size with a medium-narrow interior volume and a fairly snug toe box. While the fit feels snug when they’re laced up, that’s actually ideal for keeping your feet locked down to the midsole/outsole chassis when running—especially climbing, descending and cornering – on mild or semi-technical terrain. Combined with the great proprioceptive feel for the ground in the forefoot, the Skyfire 2 is one of the most agile and sturdy trail shoes on the market. The ride is smooth, modestly cushioned and low to the ground, but not excessively so in any category. It feels smooth, but not overly bouncy or springy. It feels cushioned, but it’s not chunky, mushy or wobbly. It feels low to the ground, but not so much that you feel every pebble. There’s just enough under your feet to provide protection and a little bit of guidance, but not so much that it gets in the way or inhibits your stride in any way.

Why It’s Great: Some minimalist trail shoes that are light or low to the ground tend to lack structure and wash out on angled terrain or sharp turns, and that often results in a sloppy sensation where your feet slosh around inside the shoes. Not with the Skyfire 2, which has a dialed-in fit and just enough structural support in its upper and lacing system to provide a precise and secure feeling even on off-camber terrain. Although the shoe is stiffened by the rock plate that’s embedded in the midsole, the shoe is still moderately flexible so it offers a good balance of propulsive snap, protection and lateral mobility. Weights: 5.8 oz. (women’s size 8), 6.9 oz. (men’s size 9) Heel-Toe Offset: 6mm (25mm in the heel, 19mm in the forefoot)

Why You’ll Love It: If you’re new to trail running or eager to run faster paces on occasion, you’ll love the agility and lightweight feel of the the MTL Skyfire 2. It’s a great shoe for up-tempo training or short-distance racing, partially because it feels like a road running shoe built for the trails. The combination of the secure fit, reliable traction and medium-depth cushioning will give you the ability to run with precision, power, speed and agility to the level that the terrain or race course dictates.

Pro: The outsole traction has a matrix of semi-sticky Vibram MegaGrip rubber with an array of mid-sized 5mm lugs around open cells of exposed midsole foam. It’s surprisingly good on just about every type of dry and wet terrain I encountered – soft dirt, wet mud, loose gravel, fire roads, long grass and sections of snow. (It feels OK running over sections of bike paths and roads, too, but it’s best on softer terrain.) The rubber provides reliable traction on rocky routes (even though that’s not where the shoe excels), while the exposed foam adds to the bottom-up cushioning sensation.

Con: OK, maybe this should be obvious, but featherweight, minimalist trail shoes usually don’t do great on gnarly technical terrain, and neither does the Merrell MTL Skyfire 2. If you’re a strong, fit and experienced trail runner, it can certainly be sufficient for most surfaces. But I have a feeling a lot of new or novice trail runners who run in this shoe on rocky mountain routes will feel like their feet are exposed and vulnerable – especially to (potential) smashed toes or sidewall abrasions on account of the minimally reinforced upper.