Note: This is another in my sequence of post-Mystery-Hunt cryptics, which started with "Still There," "Post-Game Predictions," "The Sequel," "Power Lines," "A Lesson in Cryptography," "Yet More Villainy," "Further Escapades," "Time X*X," "Honeymoon in Segas," "If At First You Succeed," "Another One From The Vault," "Next Winter: Wonderland," "DAB," "Some Extraction on the Side," "Another Campaign," "Mind The Sharp Bits!", "Through The Wood", "Newbie Toonie", "Tomezone", "Museum Pieces", "Nethermore", and "Nothing in the Nighttime"; this one was written before the 2027 hunt and refers to the 2026 hunt. "NI3," as is usual in the National Puzzlers' League, indicates Merriam-Webster's Third New International Dictionary.

Greetings, CRYPTIC researchers! As the year wanes, we're studying the multiple kinds of beings on a world beyond The Edge of January's map, at the intersection of lines (a) through the non-Euclidean Hyperbolic Space and the flat, hexagon-tiled Atlas of Mosaics, and (b) through the Monster Mash and Name That Tune artifacts:

A. Eastward. Each of 17 Eastward clues has one wrong letter, to be corrected before solving. In clue order the wrong letters, and separately the right letters, will spell out two "Attributes" of this world, matching (a) and (b) respectively; the world is a hemisphere (and thus has [Attribute a]), and the grid is a Mercator map of it whose top edge is the 89.2°N line, left and right edges join up, and bottom edge is the equator. This map's inhabitants have (i) hand weapons firing antimatter beams, and (ii) striking costumes; of the 13 other Eastward clues:

(i) The answer to each of seven must be entered with multiple letters in one square topped with a bar; the letters and bar will denote a composite antimatter particle. (These squares will form two beams of opposite charge.)

(ii) One word in each of the other six must have an item of costume (possibly broken up with spaces) inserted before solving; all costume items, as interpreted by Q. Victoria and A. Burnham, will be in one category.

For each, if there are n letters in the (i) particle or (ii) costume item, note the clue's nth letter. In clue order, the (i) letters will give a (technical) word for these types of particles, and the (ii) letters will give a (nontechnical) word for the category; the (i) word followed by the (ii) word will signify "group of life forms comes to life."

B. At the Equator. The [Attribute b] is that antipodal columns (those seven columns apart) are joined at their bottom edges, so the equator has only seven line segments (each shown twice), and At the Equator answers form seven pairs, each occupying an answer space crossing one such segment. These pairs are of two types:

(i) The two clues give answers that differ in exactly one letter. Enter this common answer in one direction in the entire answer space, with both variant letters landing on the equatorial segment instead of in a square; thus, one ("matter") answer will read in the expected direction using one variant and the other ("antimatter") answer will read backwards (from its point of view) using the other variant.

(ii) One clue yields an answer that can be entered normally, ending at a square adjoining the equator. The other, whose apparent starting square adjoins the equator, yields an answer saying what "costume" the letter in that square (determined by the crossing Eastward word) is wearing; find the letter obtained by removing the costume (e.g., L – FORTY = X or W – DOUBLE = U), and write that letter on the equatorial segment.

Read the seven equatorial segments in an eastward loop using the "matter" letters, then a westward loop using the "antimatter" letters, to get two seven-letter words forming a phrase associated with the map's inhabitants.

C. From the North. Each of these clues is simultaneously a normal cryptic clue for its grid entry (matching the enumeration) and a wordplay-only clue for a northern (1) seaborne object, (2) land, (3) city, or (4) creature (matching the letter pattern); (1–3) answers could reside below the 89.2°N line, but not (4) answers, which are of two kinds (one stated, one shown via examples). In clue order, the "northern" answers' initial letters will spell an apt phrase, which when put after B's phrase will name a song associated with the map's inhabitants.

Finally, match C's 13 clues with the 13 "other" A clues (both in clue order); if a C clue's answer is in group (n) for n = 1, 2, 3, or 4, circle the first letter of the nth word of the matching A clue. In clue order, (i) read the circled letters for A(i) clues to get a phrase noncryptically cluing the A(i) word, and then (ii) do the same for the A(ii) clues and A(ii) word. Then above one grid column, heading north, you can write phrase (ii) and then phrase (i) so the path that heads south from the top of the antipodal grid column, across the equator, and north to the end of phrase (i), thus getting within sight of those off-the-map C(4) creatures, will say who can help you research all the beings that emerge on this world from October through December.

EASTWARD

AT THE EQUATOR

16. Ruler of Germany and India emptied larch wood Wii boxes (2 wds.)
28. At the BBC, make forceful finale from Martin Amis into something colorful [NI3]
32. Twice force-fed person earth's puffy dishes
34. Danaë swims channel (3 wds., abbr.)
36. Full crew of topmen Clem organized
37. Craps bet whose true odds are 10:1, even assuming Mercury (ole!) is retrograde (2 wds.)
38. Statement having the superficial aspects of "Phenomenal face!" for instance!
39. Polish-English yokel
40. Deer eating date and fig — and horse, which is a struggle (2 wds.)
47. True, I'm due to fuse a fusible isotope
49. Like some trousers whose bottom moves up seven rows
51. Explosive substance Alice's cat could put into one's ear
52. Not so much as 50 shillings received by Mr. Frome (2 wds.)
54. Eggy beverage has slight zip

FROM THE NORTH

1. Briefly Daniel (centrally towards the top)'s on ER (2 3; _A_C_R)
2. Offbeat Thorpe trusted archivists within Albion, chiefly (3 3, abbr.; _T_A_A)
3. Cheerful appended words the Castilian obstructed with lexicon's opener (4, abbr.; _P_S_L_)
5. Circling line, bit, and the last hemi-semi-encomium? (4; _L_T_E_)
6. Liquid on a TV (when attached to "Aid") endlessly, that's to appear in a mirror (4; _A_V_A)
8. Odd, tersely German real with 1 recycled? (5, abbr.; _L_)
9. Flower hiding m-shape, after rotation and bit of ritual (4; _L_E)
10. Notes re-revised with solution to x² – 201x + 200 = 0 inside for ballcatcher (6 3; _S_O_I_)
12. Redo a change with (internally) ovate entity at west of Romania (6; _N_H_R_G_)
18. Upright ht. associated with small components from unsaintly, loony Euston (3 1; _H_L_)
19. Under heading of "Numb Hit-Gal/Stark Kinswoman's No." (4 1; _M_A_)
26. Risible unperceiver to start march back with water-forming elem. (5; _U_O_P_)
31. Excited silver one's left behind part of veg (4; _L_I_O_E)