The Otter is a knife that just hits me the right way. It kind of looks like a Barlow. Its impeccably finished. Its thin and slicey. Oh and it sports a proprietary knife material (not steel): Terravantium. That recipe is one, like oven fresh cookies, that I can’t resist. But there is a big question for me, as a steel nerd: what the heck is Terravantium?

First, Terravantium is a cobalt-based blade material. Cobalt is a fascinating element with a long history. It is a metal, but one that rarely occurs in nature in its pure form. In fact, the only sources of pure colbat on Earth are from meteor strikes. The reason is simple—pure cobalt reacts with both oxygen (which is in the air) and chlorine (which in the water). We can create pure cobalt through an extraction process, but most cobalt is an alloy. Cobalt has long been known for its resistance to heat and corrosion and because of these properties it is regularly used in medical implants.

Terravantium is a form of dendritic cobalt. Dendritic cobalt is a very hard non-steel that has excellent corrosion resistance. It has a long history in the knife world. Dave Boye has been selling “mariner” knives with dendritic cobalt blades for years. Stellite 6K and 6B have been produced for years and they are, on balance, mostly cobalt. Talonite is also a cobalt-based blade material. How these differ from Terravantium is difficult to determine because there is no data sheet for Terravantium. The Terrain 365 website indicates that Terrvantium differs in how it is processed: “One of the distinct properties of Terravantium™ is that we do not roll out our investment cast bar stock or blades which separates the carbide crystals. The microscopic carbide crystals retain their original structure resulting in longer lasting and superior cutting performance.” Is Terravantium regular cobalt alloy that is processed differently or is it a new recipe? Its not clear. Fortunately, I am not a metallurgist, but a knife reviewer and I all need to know is the answer to Doug Marcaida’s catchphrase question: “Will it cut?” The answer is 100% yes.

Here is the product page. There are two different Otters—the Prometheus Design Werx variant with the kraken logo on the ricasso and exclusive OD green G10 handles and the Terrain 365 version without the kraken. One is very limited. The other is somewhat limited, and I went with the Terrain 365 version for that reason. The Terrain 365 version has three handle materials: black, gray, and carbon fiber. All of the Otters with G10 handles (including the PDW exclusive) are $267. The carbon fiber version is $299. This is the first written review. Here is a video review. Here is my review sample (which was a birthday present and mine to keep):

Twitter Review Summary: Strikingly good, but in ways you aren’t expecting.

Design: 2

In the world of modern traditionals there are the X Series of knives which are far more modern than traditional. Then there are knives like those from Italy where they are barely traditional at all. The Otter falls pretty close to the opposite end of the spectrum, with a bail, a nail pull, no lock, and a pleasing traditional blade shape. Only the handle material, in my case G10, and the blade steel keep it from running with the Case Pocket Trapper. That combination works well here as it helps accentuate the blade material, which is the star attraction. With no flipper to fidget with and no lock to add bulk, all you get is a great cutter. Since that is the main purpose of a knife, this is a good thing.

The performance ratios are decent. The blade to handle ratio is .76. The blade to weight ratio is 1.11. These aren’t record breakers but they are very good. It also tells you that the choice to go lock-free was the right one here. This is a lean, mean cutting machine.

Fit and Finish: 2

Its not a complex knife by any means, but what is here is supremely well crafted. The contoured handle is excellent, the bail is just the right level of tight, and the finish on the blade even and clean. When deployed the backspring is clean and flush. Over and over again, the Otter is simply and nicely made.

Grip: 2

Don’t fool with grip inserts, finger scallops, or any other grip crutches. Make your handle nice and simple and leave the G10 with a small bit of texture. Your hand will do the rest. That seems like the Otter’s plan. We have been making good, grippy knives for at least ten centuries before Tec-Track was invented.

Carry: 2

There is no clip, but the bail works well if you want to attach a lanyard. I prefer to carry the Otter sans lanyard. It is slim and very polite in the pocket. There is a reason traditional knives, even now with modern knives, still ride in a lot of folks pockets—they carry brilliantly.

Steel: 2

I love the blade material. In fact, the Terravantium is quickly moving up the ranks as one of my absolute favorite cutting materials. The corrosion resistance is great and all, but it is the long lasting, aggressive, toothy edge that has won me over. Its so good, as a matter of fact, that I would still like the material even if it wasn’t corrosion resistant. The fact that it is, well, that makes this something extraordinary.

Most cobalt blades cut for a long time because cobalt sharpens to a very toothy edge. Those microserrations make for a very aggressive cutter and because there are so many of them, the knife feels sharp for a long time. I have used the Otter in a lot of tasks—box breaking to food prep and it really excels. In fact, it even handled tasks I normally reserve for serrated kitchen knives with ease. For example, when I make chestnuts, I usually score them before blanching and then roasting them. Most of the time I use a small serrated knife as the hard, slick shell is very difficult to cut with a straight edge. But here, with the Otter and it is microscopic teeth, I could saw through the husk in no time flat. No other plain edge knife has been able to do that like the Otter has. The fact that I can thoughtlessly clean it off has made the knife my go to food prep tool, even in a kitchen full of actual kitchen knives (yes, I am testing it out…).

I am floored by the knife’s performance and I love the cobalt blade. Its combination of properties makes it one of the nicer knife materials out there.

Blade Shape: 2

This is an exaggerated spearpoint, a bit more bulbous than normal, but it also has the fortunate side effect of making the knife less “daggery” and scary than it could be. Traditional knives are more socially acceptable and this blade shape makes them even more so. It also happens to be a good cutter, too.

Grind: 2

The cobalt has been ground very, very thin here and the result, as always, is superior cutting performance. The grind combined with the material makes this one of my very, very favorite slicers. If you want a pocket knife for cutting you won’t find something better. This knife is the first knife I have used that clearly outpaces the Perceval. There is a new Cut King and it is the Otter.

Deployment Method: 2

Its a slipjoint, so it won’t open with one hand, but get over that you will be rewarded with an excellent walk and talk. Keeping it simple might make this a slow open, but it is a good one.

Retention Method: 2

If you are new to knives then bails might be new. The nod here is to the maritime traditional, where bails were more popular than lanyard holes for simple reasons (easier to thread with cold wet hands…). Given the blade material and intended use, the bail is both effective and a clever wink to a specific piece of cutlery history. Unlike other bails on older SAKs this one is not free swinging, so the chance of a blade denting accident occurring very low.

Lock or Blade Safety: 2

No lock of course, but with a strong positive half stop only a moron would hurt themselves when using this knife. I do like the fact that like with all aspects of traditional knives, the halfstop makes the knife more socially acceptable. No clacking lock or snapping flipper.

Other Considerations

Fidget Factor: High

With a pleasing texture on the handles and a smooth pivot, the Otter is not as fidget friendly as a flipper, but it is as good as it gets for a slipjoint.

Fett Effect: Low

With G10 and a blasted blade, the Otter is not likely to show age at all, and with cobalt being rustproof, don’t think about conjuring a patina on this knife.

Value: Low

Well made, niche products aren’t cheap. The Otter, like the Ariel Nomad, is about as narrowly designed as it gets. So no, its not cheap. The weird thing is that the Otter, by focusing on simiplicity and quality moves out of its niche comfortably and makes a good general utility knife.

Overall Score: 20 of 20

With a laser focus on cutting the Otter is that odd niche product that is so good that it transcends its narrow intended use and becomes a broadly useful tool. This knife cuts like nothing else I have used and while the corrosion proof blade material is the headline grabber here, its the cutting performance that keeps me coming back. I am holding off on a perfect score because I haven’t had a chance to see how the cobalt blade ages. There are dire warnings about prying with cobalt, but seeing as I never pry with my knives, I am not worried. The knife’s pleasant fit and finish are also an unexpected bonus here. Sometimes knives with “headline” features ignore the fundamentals, but not here. The Terrain 365 Otter is an excellent blade and a relatively inexpensive way to get a knife with Terravantium. I wish there was more data out there on Terravantium because I like data, but the reality is this knife cuts well and the data is just ephemera once the cutting performance has been established.

Competition

There are lots of high corrosion resistance steels out there and some are better than others. H1, in my opinion, is not worth the bother. I have used a few of these knives and unless they have serrations they just don’t cut well enough and long enough to use. LC200N, like found on the Spydiechef, is at the opposite end of the spectrum. It is one of my favorite blade materials available and the Spydiechef, like the Otter, is an amazing slicer. I am not sure which I prefer—the Spydiechef or the Otter. Benchmade used to use a steel called X15TN, but I never got a chance to use it. I am really struggling for competitors. The Spydiechef is not really a competitor—its significantly larger than the Otter. Perhaps the Native 5 in LC200N—smaller frame with a corrosion resistant blade. The problem with the LC200N comp is that cobalt seems to have a toothier and longer lasting edge.

Amazon Links

Purchasing items from links below helps keep the blog 100% independent:

Spyderco Spydiechef

Spyderco Native 5 in LC200N