This disc started out exactly like I wanted - a fast Wraith, however it soon became way to flippy. For about 1 - 2 months it would fly perfectly for me. Thrown flat (RHBH) it would slowly drift to the right and then have a reliable fade left. But after a dozen or so rounds it became super flippy and not as much reliable fade back. It soon began to require precise angle control or else you would get a disc that would flip over and cut roll. 

I would say the turn is -2 and the fade is 1.

Kastaplast Grym

The Grym from Kastaplast 

I picked this disc up looking for a somewhat flippy driver but with a little more stability then my Shryke. That's not what I got but that doesn't mean it's a bad disc by any means.

Plastic/ hand feel

If you have thrown Kastaplast's K1 plastic you already know.... this is the best plastic on the market. Very durable with a great feel to it.

The mold it's self feels great in the hand a shallower disc then some other drivers out there.

Flight

out of the box this disc on a flat release has no turn for me at all it goes dead straight for about 300 ft then starts to fade left quickly on a rhbh finish about 325 to 350.

on hyzer release it will flip up for a short time ride staring and finish left

On anhyzer it holds the angle for a short time and then comes back to finish left.

Final thoughts

this disc wasn't what I thought I was getting when I bought it but I can see it easily taking over the spot in my bag that I currently use a wraith for because it feels great flys straight with a good left finish and I can flex it if I give it enough power. I actually really like the disc and would have given it a five but it was so different then the flight numbers I felt it should get a 4 simply because if you are looking for flight type it isn't what you will get.

I have read conflicting reviews on the stability of the disc some like me it's much more overstable and others say it's very flippy I don't know if it has to do with different runs or just arm speed. The two I picked up have different flight ratings one is 13 5 -2 2 and the other is a 13 5 -1 2 and the13 5 -2 2 has a puddle top to it where the other doesn't but both fly the same for me. 
 

All in all I like it a lot and recommend it for anyone throwing 300 to 350 and wanting a straight flyer with a reliable finish and if you throw farther then that and you want a flippy driver it might be what you are looking for.

Love Kasta, I've switched most of my bag to this brand because the plastic is the best. 
 

Grym (K1 172g) is the flippest disc in my bag straight off the shelf. not what I was expecting but actually a lot of fun. Good for 60% power throws, easy standstills, or rollers.  Similar flight to my D4 400 but a shallower disc.
 

perhaps there's some variation on the runs because I've seen reviews here similar to mine and others on the opposite end of the spectrum. Either way, I'm sure you can find a way to incorporate it into your game. 

This disc was crazy under-stable for me out of the box. I cant throw it flat or it'll turn and burn unless I throw ~60% but I can put as much hyzer on it as I want and get it to flip up and still turn which is actually really fun. The plastic is awesome and the depth is nice. I wish it was just more stable

Amazing disc. Definitely a bit more understable than the flight chart shows. Great for big flex lines with some height.

Another great disc from Kastaplast, this one is of course for the big distance drives, once you have this one dialed in it is extremely accurate, not as much fade as a Wraith so once i compensated for the fade difference i can literally park this thing on some longer holes i was never able to reach.  This disc is shallow and flatter than some of the other big distance drivers from most companies, of course the plastic K1 is the best, i don't think there is better and the best plastic from other companies are the ones that are trying to emulate the always fantastic K1.

If you have Kastaplast in your bag then you already know what to do, buy this bad boy and you will not be disappointed. This is a straight flier with "lots" haha of glide, goes perfect with a lots, Gote, Kaxe‌ and Berg. Just go ahead and do yourself a favor and get it!

This is a great LOOONG flying disc from Kastaplast. However my only issue was that it was a little too shallow for me. I could be all onboard with Kastaplast because their plastic blend is top notch, IF they made some minor tweaks on some discs. Just beautiful plastic.

I was getting this out 375 to 400 and it was so glidey and smooth flying.  

This is my max distance driver currently. I do not have the arm for a destroyer. I think the flight numbers are pretty accurate. The K1 plastic is amazing. This thing gives me a full S flight when thrown hard and flat. I am not a power thrower, but I can touch 420-430 with this disc. I absolutely love it. I am buying 2 more just so I have spares. The plastic is crazy durable. I have thrown it probably 100 times, and it shows no signs of beating in. If you like to beat in discs, this plastic is not for you. If you are pushing that 400 mark, but just cannot seem to get over that hump, give this a try. I love the Grym.

Too hot for my arm.  Nothing wrong with the mold, but I don't have the punch to put this disc out there.  Something to work towards, but not the first disc I would consider.  K1 plastic is the best in the market, and Kastaplast makes a mighty fine disc.

The Grym is a stable high speed distance driver from Kastaplast, despite the claimed flight digits.  I know they have engineers simulating their flight path so they feel very confident about the -1.7 turn, but I have to respectfully disagree and call it about -1.  I do think the fade digit is pretty accurate though, because for me it fades just a tad less than a destroyer would.

You all know that Kastaplast makes probably the best feeling plastic there is.  K1 is actually my least favorite out of their 3 plastics but it's really nice for drivers.  Nice and firm, but still very grippy, which is great for sidearm because I want to be able to get a nice firm thumb pinch.

I gave this disc 5 stars because I love the grip for sidearm, and I threw my farthest drive ever with it.  I primarily drive sidearm and I'm usually in the 310-325 range on a good one, but on one drive recently "the stars aligned" and I threw this guy about 425 on a hard high flex line.  Of course top level pros can throw far with any disc, but for me (an average intermediate) the shape of the disc and the grippiness of the plastic is unlocking about 25-50 extra feet on average for me.

This disc is quite a bit more stable than the flight numbers state for me. I must be growing into that speed still. Although I can get the full s turn out of a Shryke. Of course the k1 plastic feels amazing. I'll definitely be doing some field work with this beauty.

Threw this disc in K1 plastic.

Feel: Kastaplast K1 has a very unique feeling to it. The rim doesnt have that usual ~90 degree angle on it, but the plastic is so grippy that it still feels great. The rim is quite shallow, which suits me perfectly. 

Flight: Out of the box it flew a bit like a slightly less overstable Destroyer or like an out of the box DDx. I could easily hyzerflip it to a slow turn to around 500 feet. 

Conclusion: The Grym is a very interesting disc. It is slightly too flippy to replace my Destroyer or DDx in my bag for the course, but I'll gladly throw it on the range. I suggest trying it out if you're curious. I'll have to get my hands on the Grym X. I have a feeling it might make the bag if it's anything like an overstable Grym.

To start with, everyone is right, the K1 plastic is the BEST PLASTIC ON THE MARKET!  It holds up amazingly and is the absolute perfect grip/feel in the hand!

As for the flight, this is my number 1 distance driver.  I used to throw destroyers but when I got this, it immediately flew like my beat-in destroyer and with the better feel in my hand, it got the top spot in my bag.  I do have a pretty strong throw and with a little time, I can this disc to flex out for huge flights.  That being said, with my arm I do have to be a little careful into headwinds, otherwise I can get full-out turnovers that never come back.  I haven't tried the Grym X yet so maybe that can fix that issue.

Overall, I love this disc, it works wonders for me!!

It's super overstable, as a forearm thrower it doesn't break left as easily as a Stal would. Huge drives as long as I put more than usual anhyzer on it. I'm sure with some time, this is gonna be a massive addition to my bag.

I love this disc. If you throw destroyers or outlaws the description is perfect. It is a "beat in" destroyer. If you have a high arm speed I would suggest not throwing into a headwind unless on strong hyzer. Kastaplast has some amazing stuff with both the grym and the grym x. Seem to be faster than my destroyers but can't take my boss spots. 

Lets start with the positives.  As in every Kastaplast review the plastic is the best on the market.  This disc has a very thin profile, with a wide but not sharp rim.  I liked the feel and was pumped to throw it.  But I threw this into a 20+ mph head wind and it still never turned.  It flew straight with a reliable fade at the end.  This is a stable to slightly overstable driver.  I was throwing this along side my Lucid Sheriffs and they had about the same amount of dump, but this one didn't have near the same distance.  Less glide and the zero turn is why. I threw this with a tail wind shots and it performed the same as the headwind shots.  So it is a consistent disc.  This is definitely not understable.  This is a stable to slightly overstable disc (if you have 350+ power).  That doesn't make it a bad disc, just mislabeled.

K1 168g. As always the K1 plastic is amazing. However, I was expecting an understable or stable distance driver, which is not what this is. This is a initially straight flying driver that finishes with a heavy fade. While I like the disc, I have a boatman firmly in that spot in my bag and I prefer those to this disc. This disc is also super shallow and while I got some nice lines with it, the rim depth was less than what I prefer.

I want to start out by saying i love this disc. but i would agree with some of the previous reviews in saying that this disc is defiantly not under stable. i normally have 350-400 distance with drivers. this disc goes straight a majority of its flight then has a gradual forward fade at the end. like i said i love the disc but its not understable. great for hyzers and forehands

The Grym is all about distance. I have noticed an average about 20-30 extra feet over my regular distance drivers (Wraith, Katana, etc.) But the extra distance doesn't come easy. It takes a really big rip to get this to turn. For reference, I can throw about 380 on average and on occasion over 400. Most of the time the Grym throws very straight with a hint of turn and heavy fade, but into a slight head wind or with a lot of power I can get it to make a big S. Overall its a great disc. 

Beautiful!

I got a K1 Gyrm from my favorite boutique disc golf company, Reptilian Disc Golf, and it is magic! 

First, the K1 plastic is translucent, shimmering, and looks beautiful. The flight plate has some give - more than Innova Champ, but is rigid enough to feel solid in the hand with a string power grip. It feels similar to Discraft Z or Trilogy opaque plastics, but with translucent finish. 

I usually drive with a Prodigy D2/D3, and this fits right along with them. In initial field practice, it was a touch straighter than a Prodigy D2, a touch longer than a D3. A very good amalgamation of the two. 

First hole I drove this with is a 500' field, guarded on the left side, tall grass to the right, that has a few trees, several grabby bushes, and ends with a significant uphill on the last 100'. Usually, I'm happy to get to the base of the uphill with a clean drive. However, the Gyrm turned right over the grass, held a long straight flight, then faded back with a solid finish and HUGE SKIP! I ended about 40' short of the basket - up the hill. 

Meh. Must be a fluke. Three holes later, another 500' hole, this time completely flat, wide open fairway with a guarded basket. Full pull - flat release - the Gyrm flew out with a quick turn and then came back flat quickly again. It held flat for 75% of it's flight, then faded back right at the basket and had another crazy skip and ended about 60' from the basket. 

I do not have a power arm by any means. 400' is usually a great drive for me. However, this disc just clicked and flies further than anything I've ever thrown in 13 years off playing. 

If you have a moderate arm and can reach 375'-400', try the Gyrm. It gives more distance with less effort than trying to flex a more overstable driver. 

Agreed with previous reviewer. This is not understable. i have to go full RIP mode to get it remotely going towards the right and by then its not a path i wanted it to go to.  I find it to be a hard disc to sidearm given the small depth the disc provides the finger. Plastic feels great though. I give it 3 stars because of misinformation.

The text print on my 175g K1 GRYM says that this disc is "understable." When I tried throwing it backhand this disc was not anything I would describe as remotely Understable for my moderate power. For a backhand on a level release the GRYM immediately starts hyzering out and fading left. While this disc is too much for me backhand, I absolutley love it for forehand throws. 

The GRYM is a very thin flat disc with a low profile. The K1 plastic feels amazing. When thrown sidearm, I would say this disc is slightly more understable than my Westside Worlds, but I am able to release it more consistently due to the flatter top. After release this disc will turn for a nice S-curve and then always fade back. For now, the Grym is the first Kastaplast disc that has made my permanent bag.