alright the theorycrafting is real on this one.

basically homestuck works on sets of 16. because of the 16 possibilities of 2 letter usernames using ATGC. 4 kids + 12 trolls, 4 post scratch kids + 12 dancestors. all neat sets of 12 that fill out all 16 possibilities.

my guess is beyond canon will fill out another set. we know 4 usernames so far from the nymphs and from the arrow(===>) we can infer theres 6 of them total. theres also the 4 omega kids. how would the set be filled out? +6. my guess is either the nymphs get a scratch or we get another set of 6 from whatever species dirk cooked up, or a mix of the 2(maybe not all 6 of the ===> are nymphs).

so my theory is this: omega kids will not scratch. nymphs will. 16 filled out neatly