SCP Foundation

The object is currently held within a securely locked concrete cell.

Describing an SCP as "the object" is sort of an old-fashioned convention and would probably turn off a lot of modern readers, it might be better to make it the SCP numerical designation.

This cell can only be opened via level 3 or higher access, or permission from a higher level researcher.

No other containment procedures are required.

Both of these lines don't really mean much, and the second one is false because you have further containment procedures after it. I think you could remove both of these lines without losing anything.

Currently, 2 instances of SCP-XXXX-2 exist. These instances are secured in hermetically sealed cells at site-[REDACTED]. Growth of SCP-XXXX-2 is to be suppressed by rapid controlled exposure to extreme temperatures of up to 200-300 degrees Celsius every 5 hours, for about 10-15 minutes.

The redaction in containment procedures is also considered to be bad unless there's good reason for it, since you need to know the containment procedures in order to contain the SCP. Especially since it's just the facility it's located at, whomever reads this in-universe would presumably know that so there's no reason to redact that information.

SCP-XXXX is a severely worn kitchen knife coated in rust. The blade is constructed of steel, and measures approximately 10 inches. The hilt of the object measures exactly 5 inches. The object possesses engravings on the hilt which read "To be bound by blood is to ascend."

The specific measurements don't really tell us much, although I suppose since you don't have a picture they give an idea of how large a knife we're talking about. Apparently a very large one. The engraving on it reads kind of self-seriously and goofy in my opinion, I get that you're trying to go for something spooky but it doesn't really work out that way.

The effects of the object are activated through a specific process. The process required to engage activation of the objects effects was discovered in the contents of the unlabeled tape found with the object. Upon replication of the process depicted in the footage, the objects anomalous properties were confirmed.

The information contained in these sentences could probably be consolidated into one. Additionally, not getting right into the effect of the SCP is likely to turn readers off. it's usually better for the narrative to get right into things, to start at the beginning, so you can hook the readers into wanting to know more about your SCP after they know the effect.

The contents of the tape feature 2 individuals of indeterminate age and gender engaging in a ritual, in which the 2 unknown individuals use the object to slit their wrists. The individuals then proceed to consume one another's blood. The tape ends after a black screen featuring the same text on the object in white appears for 10 seconds. After replicating the process using the object, an instance of SCP-XXXX-2 is successfully created after 24 hours.

The effect still isn't present and we're halfway through the article. The description of the video is also pretty vague, just two people killing themselves with unclear means. It plays into horror tropes which have been explored pretty thoroughly on the site, suicide, violence, and haunted videotapes. Specific description of the video content to make it stand out and more interesting to read would be better.

SCP-XXXX-2 is a large mass of skin and muscle, which shows no signs of sentience or consciousness. The mass will steadily rise and fall, as if it is "breathing." The mass, while not being toxic or directly harmful, can prove to be dangerous if left unattended. If left unchecked for prolonged periods of time, the mass will grow at an accelerated rate, quickly covering the walls, floor, and ceiling of a room. The mass has proven to be able to completely cover a small room in less than 2-3 hours. Extreme heat has been proven to be highly effective at preventing and reverting the growth, but cannot destroy SCP-XXXX-2 completely. As of now, no known methods have proven to be capable of completely destroying or killing the mass. DNA tests have shown that, as expected, the mass consists of the two subjects with which the ritual was preformed. After testing the first instance, the two individuals involved were discovered to be Mr. and Mrs. [REDACTED]. It is as of yet unknown how the couple came into possession of the object.

This feels totally disconnected from the rest of the article. So the totality of this is that there's a haunted videotape of people killing themselves that creates a viral flesh-mass? There's a little bit of storyline in that the masses are the same people featured in the video but that's not enough. There's no story here, no narrative, nothing of interest.

It might be better if it had a more literal connection to the video, like if it caused blood to fall out of your television set in a Shining fashion, maybe making a statement on television and violence, but that would require significant reworking. I will say that your tone and writing is mostly good enough, outside of a few old-fashioned writing tropes I mentioned earlier, so with a stronger idea you might be able to make something cool. I would personally write this off as a practice SCP and move on to something else.

The videotape is very important in the article, but kind of pops up out of nowhere. I would recommend giving the videotape its own SCP designation (SCP-XXXX-A or something).

Similarly, it could improve readability if you split of some sub-sections of the description (like "Discovery", etc., or a log describing the tape). I don't think all articles need these things, I just think it would improve the flow of your specific article.

After replicating the process using the object, an instance of SCP-XXXX-2 is successfully created after 24 hours.

DNA tests have shown that, as expected, the mass consists of the two subjects with which the ritual was preformed.

I feel like these two sentences are supposed to relate to each other, that we the reader will naturally assume that the two individuals are merged into each other.

But just reading the first sentence, there are several possibilities: SCP-XXXX-2 could be a horrible blood child, a demon summoned from another realm, etc. I know it's not supposed to be all written out plain, but I feel like, to instill dread, a little more hinting could be used. For instance, you could say that SCP-XXXX-2 is created and the two individuals are consumed, or somehow mention that the individuals no longer exist separately.

The home still contained the couples belongings, though the neighbors report they had been gone for 2 months. In the upstairs bedroom. The object was discovered, along with a camera, the tape, and the first recorded instance of SCP-XXXX-2.

A few typos here: couples should be couple's. The phrase "In the upstairs bedroom." shouldn't be its own sentence.

The contents of the tape feature 2 individuals of indeterminate age and gender

Why are they indeterminate? It's unusual to have a tape where you can't guess age and gender at all. Is the tape blurry, or are they wrapped up in robes?

This borrows from a lot of common tropes: it's a weapon, it's involved with cultists, there's a ritual creating a Sarkic-like flesh mass.

Because of that, I really think working on making the structure 'look nice' could help you. Look at the top SCP articles this month, and see what they do in terms of paragraph length, addenda, and structure. It really improves an article!