@LepaVida I’m working with this exact strain right now, they’ve been vegging for just shy of three months. Here is some basic X18 info for you:
The original X18 breeder is The Chemist…well, technically the Pakistani tribesmen of generations past, but The Chemist (a friend of Tom Hill) is the one that got it in seed form to California pre-70s, and selectively bred it to heirloom status. From there, it was brought into the mainstream by Tom Hill, who deserves the most credit for keeping and preserving this strain for the masses:
As stated prior, probably the most well-known modern day cut of X18 is Raco’s XVIII (there’s threads about this cut documented on other forums).
DNA also did a reproduction of X18 based on Raco’s cut, although under dubious circumstances (there’s threads on other forums outlining the history behind that, no need to get into it here). As far as I know this was a 1-1 selection of Raco’s female crossed to an X18 male. I believe DNA have also done X18 fem releases? But don’t quote me on that:
I am growing X18 as the backbone of my current breeding project. I acquired some authentic X18, original Tom Hill stock, from my friend and business partner, whom I believe acquired them from Breeder’s Retail (run by Chimera for those of you familiar with that breeder). According to Chimera, he acquired the stock directly from Tom Hill, and it was stock from Tom’s last reproduction of X18, which was 2005-ish? Again, apologies if I am wrong on the dates and facts, feel free to correct me if wrong. Chimera is known to keep an extensive genetic library and to have the facilities to properly preserve seed stock to scientific standards, so this old stock came to me in pristine form. Of 20 seeds, I successfully germinated 18, so a 90% germ rate on 12+ year old seed stock…impressive to say the least.
Tom Hill was well known for his breeding techniques, and when it came to selections, he used massive numbers of plants for his reproductions, in order to get the full range of genotypic expressions and ideal selections for his reproductions. I am nowhere of the scale to be able to do that, but regardless, I believe strongly in the preservation of endangered genetics and wanted to at least attempt a reproduction as completely as possible, with the limited resources I have available. So for my X18 reproduction, I will be keeping and using all 18 specimens. The one exception I will make is if I notice any hermaphroditic tendencies in any of the plants, then that individual plant will be culled. I do believe that an 18-plant reproduction will hopefully be closer and more true to Tom’s selections than the 1-1 production produced by DNA. That is not a knock on DNA at all, but just a highlight of what I am trying to achieve with my own work.
X18 is said to have quite a few unique traits for a pure Indica from Pakistan. It’s said to be more NLD-leaning than BLD-leaning (Pretty much all genotypes of my 18 plants confirm this). It is also said to be stretchier than most indicas (I will be able to confirm this in a few weeks when I flip to flower). The chemotypes of X18 are said to range from sour apples, to pears, to skunk, to cheese, to chorizo. I can concur on some of those, even though it is only late veg for me; the full range of chemotypes should be more readily apparent once I’ve entered the flowering stage. A few definitely stand out as skunky and cheezy. A few I would say lean toward the “apple/pear” spectrum, but these are softer and harder to pinpoint (I try not to be biased by other reports, so I won’t say definitively until it really stands out to me). One in particular is very low odor. But I can say the smelliest ones are SUPER sticky on the stalk, and may turn out to be extremely resinous (fingers crossed). And when evaluated as a whole…and disclaimer, I really HATE to use this word, but it does describe this family of plants perfectly…you definitely can tell right off the bat that you’re dealing with “kush”, as those earthy gas tones stand out instantly. If someone never smoked cannabis and wanted to know what “kush” smells like, I’d direct them to these plants as a base example. TLDR: nice earthy gassy tones, some leaning cheesier, some leaning skunkier, some with a very soft, but fruity, apply head, and one very low odor.
One thing that’s been pleasantly surprising is how well the X18 cuts root in rooters. I took a bunch of “throwaway” cuts, meaning, plant material that got chopped int he course of thinning and lollipopping, and popped them in rooters, just to possibly keep a few of the original moms around. Pretty much all of these cuts have rooted within a week, some within 3-4 days, which I can’t say about a lot of strains. That on top of my cloning tech being really bad 
shows how good these genetics are, at least from a vigor perspective.
In addition to the X18 repro, I’ll be doing a bunch of outcrosses to some modern day hybrids, and some classics, to see what we get and to see what the landrace genes bring to the table when outcrossed:
88G13HP (Hazeman) Released by Hazeman but widely known because of ndnguy
LA Pure Kush (Hazeman) I’ve asked Haze about the male parentage on this seed stock, as I thought LAPK was clone-only? Never got a response.
Stardawg IX (Top Dawg) Speaks for itself. This Chem offshoot should mesh well with the Paki kushiness.
C99 (Bros Grim). I need to check with my friend to see where he sourced this. He told me it was original stock from 1997. @Baudelaire it looks like you also have the same? Did you have any orders come from Mass lately???
Nigerian Haze (Karma Genetics). Not to be confused with Top Dawg’s Nigerian Haze, this is the Nigerianc x White/A5 Haze cross.
Whitey (THC Development). I talked to the original breeder. This is indeed “The White” in seed form. He found a rare S1 Male in the White S1 release by OG Raskal. That male was hit to the elite White clone, making Whitey.
Afghan Kush (clone) this was sourced from a buddy in Western Mass. Grows really strong and vigorous. I had originally popped a punch of PCK by Cannabiogen for a Double Paki cross, but none of those germed. He offered this clone to me to do an Afpak outcross as a consolation. I gladly accepted.
Strawberry Fields (clone) sourced from the same bud in Western Mass (which has had the dank for decades BTW, they’re miles ahead of Boston and other parts of the state in general). Story behind this particular cut is it was held tightly by one particular grower in Western Mass for a couple of decades, old school guy apparently, and with the advent of legal RMJ in the state, he decided it was time to spread it out to some people so it didn’t disappear. She’s definitely and older cut that’s starting to show her age and is extremely hard to get rooted. I may not be able to keep the mom around, but I’ll have a Strawberry Kush-type outcross as a consolation.
Lemon Tree (clone) sourced by my business partner who stated it is the verified, original Cali cut, not an S1. Going for a Lemon Kush-type outcross with these. WIll work these in-house to see what comes out of the progeny.
Blackberry Kush (clone) sourced from my buddy that runs an edibles company and is heavily connected. The smell on this one blew me away (I got it about 3 weeks into flower). I immediately put it to re-veg and took cuts. Now that the cuttings have rooted, I’m going to throw it in the flower tent and hope for a few beans. This one is for my personal stash, if I get something special from the progeny I have a very special project in mind
I’ve been lazy lately. I’m supposed to make a thread documenting this current project and its status, so I’ll try to do that sometime within the next week, plus pics. I do want people to be able to verify the grow and the seed production for the sake of transparency and good breeding practices. And I also want to be able to coordinate with folks here to get some testers in their hands once the project completes. So please look out for that over the next week or so, in the meantime, you can find pics and updates on my IG (@buryseeds).
@LepaVida hopefully that wasn’t too much of a thread hijack 
and hopefully you found that X18 info informative. I’llt ag you on the X18 thread I make, when I make it, so you can follow along and see updates / progress as things roll… 
-Bury Seeds