Ground Plastic feels great for putting. Great price point and very dependable flight and feels great in the hand. I also have a
Storm plastic for throwing and it has a dependable fade on the flight. Will recommend for anyone, I bought a bunch to practice.

This was the first disc a fell in love with and I will only putt with this ever 

The Ground-plastic Knife has a good grippiness to it and putts well as one might expect. No issues there. For throwing farther, I found that it kept ending up in pretty tight formation with my 2/3/0/2 comparison putters rather than the 3/3/0/2, so for that reason I've listed it as a 2-speed to match. I do prefer the Storm plastic because of its durability, so if just putting, this disc should hold up pretty well without a lot of change in its flight; but if using it for longer throws, it's likely to get beat in quickly and fly a bit differently (same thing happened with my base-grade Keystone).

Good feel on this disk, the rim is not too thick. Love the Vikings stamp that I got with it! Disc is great for shots that need a little fade at the end.

I've been on a quest for the perfect putter for over a year. I've been through daggers, judges, emac judges, aviars, wizards, runes and penroses.

I can say fairly confidently that my search is over. The knife has hit all the marks for me. 

My go to putters for the past 6 months have been my judges and emac judges. They feel solid in the hand when putting and for longer shots a little hyzer flip has them straight as an arrow. However, I live in a fairly windy place and anything outside of 50 feet in the wind made me feel less confident with them.
I searched for a more overstable putter to use in both the circle and approach shots. I bought a few penrose putters and I didn't like the deep rim and they would still turn over with decent power (200+ feet). 
I've come to realize that I enjoy shallow putters for circle putts, the rune was great for this. It's glidey and it's profile is quite slim. 
The knife is an overstable rune. In the circle, it handles pretty similarly with maybe a little less glide. On approach/tee shots I can put power behind it and I've yet to see one turn over on me. I threw a 300 foot tee shot flat, and it stayed straight and faded a small amount at the very end.

My only wish is that they some additional plastic types. Something similar to Dynamic Discs classic blend or Innova's Gstar. The ground plastic is decent on grip, but it gets beat up fairly quickly

The knife is a great disc for around trees putt or a longer upshot that you need to hyzer. The knife in ground plastic is good at gripping the ground and is very durable. I prefer to put with the rune over the knife but both fly about the same it just depends what feels better,

First off, two things. I have been deeply, deeply impressed with the discs that Viking has been putting out. Deeply impressed. That's a bit of a disclaimer, and something of a warning to take what I say with a grain of salt (If you're a pessimist) or take these words to heart and even get expedited shipping (If you're an optimist). The second thing is that I need to explain what I mean when I selected somewhat for beginners. I picked that because if you are going to putt with this thing and use proper form (using your wrist to spin it, relying on this spin for the flight of the disc, using more of less of this to manage the wind etc.(Super basic everything et. al) You get it)), you must understand that this discs stability does come into play. With Vikings line up, you can look at it this way. For an intermediate player, the Loki is the super over stable and wind resistant utility disc that fits the range exceeding where most would throw a putter and less than most would throw a midrange. The Loki is the definition of a utility disc. The Rune, on the other hand, is a super dome-y putter that brilliantly captures the essence of a putter. While there is a decent bit of glide to it, there is absolutely minimal turn coupled with absolute minimum amounts of fade. This makes the disc super touchy for approach shots, and unless you really nail that angle out of your hand, it is going to take however you release it and take it to heart. A millimeter of hyzer and its cruising left, possibly forever. It's just better left as a putter. The knife, however, completely and beautifully fills this gap between the two. As a primary driving putter, its resistant enough to the wind so that you can reliably throw slow placement shots off the tee, and make windy outside the circle putts just that much easier. Obviously utility discs and all that seem a bit different or intimidating to newer players, but getting a well rounded tool like this and practicing drives with it. 

PROS: A great middle of the road utility disc.

CONS: None.

Great disc, I have it in ground plastic and it is my most reliable putter. It is great in the wind and is a good disc to use for upshots and to forehand. I mainly use this disc for putting and occasionally for upshots. I feel like it grabs the chains a lot better than the rune, but I love the rune as well especially for upshots. 

This review is for the Knife in Ground Plastic. I provide another review for the Knife in Armor. I have two of these stable putt & approach beadless discs, one in Ground Plastic (170 grams) and the other in Armor (173 grams). The rim to each of these discs are the same, but the top plate are different enough resulting in different flight patterns; the Ground Plastic is flat top and the Armor is dome top. I use the Ground Plastic Knife mostly for forehand approach shots (50-100 feet) and use the Armor for backhand approach shots (up to 200 feet).

With the flat top to the Ground Plastic version of the Knife, the beadless putter works superbly as a forehand approach shot to the basket. The beadles putter allows good release for a forehand flick upshot. And the flat top gives that stability to drop the disc flat to the ground once the spin slows down. Yet this disc throws straight enough to attempt forehand makes from 50-70 feet out. The Ground Plastic has a balanced tackiness to it for grip and release. However, Ground Plastic beats up easily, so I reserve use of this disc for short open upshots to the basket. The Knife’s physical and flight characteristics of the Ground Plastic version reminds me of a Discmania P3x without the bead (so I suppose a P3). For power upshots, whether forehand or backhand, I prefer discs made of more durable plastics (such as Storm and Armor). I have thrown the Knife in Ground Plastic as power backhand and it matches the flight numbers although it might be a 3 speed disc (on the disc it says 2 speed). I like the flight and perhaps I’ll get a second one in Ground Plastic for backhand throws that I can allow to get beat up more. The dome-top Knife in Armor is not as stable as the flat-top Ground Plastic Knife, and I discuss this in my other Knife review.

If you like a flat-top putt & approach disc for short forehand upshots to the basket, give the Ground Plastic version of the Knife a try.

Best putter I have ever used for my spin putt. I can not even think of anything that has come close to this disc for me personally. The Ground plastic feels amazing in the hand. I will be bagging this as my main putter now, and I do not see it being replaced! A+ disc from an A+ company!

I don't understand why Viking Discs isn't a household name yet. I have thrown up-and-coming brands before that don't quite make the cut as far as quality and consistency among the other big manufacturers, but Viking Discs, is not that! This brand is legit! I have thrown 8 different molds by Viking Discs and I would reccommend all of them to anyone! Their plastics feel great, and the flights are amazing as well. Not to mention the sick stamps on every disc! Do yourself a favor and try some viking discs!

Now... on to the Knife. You absolutely can not go wrong with the Knife. Throwing putter, putting putter, upshot disc... this disc has got you covered. This thing flies dead straight for the majority of its flight with a slight fade at the end. The ground plastic is grippy and soft... perfect for putting as well as grabbing the ground when you throw soft upshots. This thing is going to go exactly where you throw it. Pick one up and support Viking Discs! Check out my crew's full review of the Knife (and more) here...

Judging by the numbers, I thought this putter would be a slightly overstable throwing putter. It is definitely not that. It has a consistent turn in the beginning of the flight and a huge amount of glide while in the air. It will flight back to flat, maybe, if there isn't any wind.

At first I really disliked this disc, but once I started to use it for my turn over shot, I became a big fan.

Hole #10 at Blue Lake Disc Golf near Portland, OR is a 310ft anny shot that favors a backhand turn over. I threw the Knife on a huge, glidey, anhyzer shot and it held the line all the way until it came to rest 5ft from the basket.

If you're looking for an OS putter, this is definitely not it. 

The Knife is designed as an overstable putter, and it feels just right for the job, with a flatter profile, ready to fight a moderate headwind to the basket. After throwing it around, I started to call it a "Zone Jr".  The Discraft Zone is a very popular putter / mid-range hybrid style disc with a flat top that is great in less-than-perfect wind conditions, and the Knife is quite similar, though I couldn't whip it quite as far as a Zone when driving. 

Players who like to putt with more power will find the Knife is right up their ally. If you like to putt with a loftier, gliding style, then the Knife will likely turn early and drop to the ground before you'd like. This is a disc you'd spin-putt with confidence right to the basket, plus it works great for precision approaches from distances outside of your comfortable putting range.

I probably wouldn't hand the Knife to a new player as their primary putter. For that, I'd turn to the Viking RUNE, which is more for straight, controlled putts.