2023 Winter Gear Guide

Long-Term Review: Rab Mythic Ultra Jacket

We’ve never encountered a zero-degree puffy this light and packable

Ryan Wichelns

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Price: $475
Weight: Men’s 1.2 lbs. / Women’s 1.1 lbs.
Size: Men’s, S-XL / Women’s XS-L

Men’s Women’s

Our testers have collected a lot of great down jackets over the years, which makes packing for any particular trip a matter of choosing the right one. There’s almost always an item in our closets that matches the exact warmth and packability requirements of the mission. But when our testers added the Rab Mythic Ultra ($475) to the collection this year, things got a little more complicated. That’s because it removes  the trade-off between warmth and packability that we’re  accustomed to.

Read more: The Best Puffies and Midlayers of 2023 

Thanks to a generous amount of 900-fill down in offset box walls, as well as a heat-reflective aluminum scrim (think gauze, but with the ability to bounce body heat back at you), the Mythic Ultra was plenty warm for below-freezing summits. It was one tester’s go-to ice climbing belay jacket in the White Mountains of New Hampshire, even on zero-degree days, and proved itself a fortress of warmth on top of Washington’s Mount Adams on a day in the low teens. The hood is helmet-compatible, but still hugs tight to the head even without a lid on, keeping warmth close to that most critical part of the body unlike any other puffy we’ve seen. (The hood is also loaded with down, which helps). Meanwhile, the handwarmer pockets are fleece lined and cozy—ideal for summits or the cold moments in between ice pitches. It also has a double zipper and internal dump pockets big enough for skins or a second pair of gloves. But do note that this jacket was almost always too warm to do anything aerobic beyond taking the dog for a walk around the neighborhood.

Despite the warmth, the snug, alpine-fitting Mythic weighs a shockingly scant 1.2 pounds. Most other down jackets of equivalent warmth weigh at least a few ounces more. The jacket is also ultra packable, stuffing into a storage sack slightly thicker than a 32-ounce Nalgene. We’ve never seen a jacket as warm as this one that packs so small. That’s thanks to the heat-reflective lining, which removes the need for extra down, but also to the ultralight 10-denier Pertex Quantum ripstop face fabric holding it all together. Don’t worry: the Mythic Ultra still proved surprisingly durable. We didn’t bushwhack in this jacket and wouldn’t recommend that type of use; but several testers jammed it into climbing packs next to ice screws, and it never failed.

All in all, the Mythic Ultra is our ideal cold weather summit parka, perfect for climbers or skiers who want a jacket that practically disappears in your pack until you get to the peak or have to kill some time standing around. It raised an interesting new question for our testers: When you have a zero-degree puffy that’s just as light and packable as lesser insulators, is there a reason you wouldn’t take the warmer one?

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Lead Photo: Kevin Zansler

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