# Little cryptic with no words involved

ACROSS:

?) Around the world - almost the answer to reversed scary room.
?) Poker deck, oh, for poker deck with 20 more squared with 20 more.
?) Smaller beast is lone, beheaded within infamous order.
?) Three rightmost one dropped just a decade from XXth.

DOWN:

?) 5th Smith holding signed declaration goes down, gradually.
?) A prime empowered its predcessor, and ate one, too.
?) Computer science, the one with mixed up weed.
?) Note: squared perfection is perfection.

• Is "pocker" deliberate, rather than a typo for "poker"? Apr 30, 2019 at 15:30
• @GarethMcCaughan dang it Apr 30, 2019 at 16:00

The grid is:

8 0 4 1
7 8 9 0
6 1 6 2
5 2 0 4

Around the world - almost the answer to reversed scary room.

8041: 80 (days, Jules Verne) + one less than 42 (Adams) but I don't understand the "reversed scary room" bit; the obvious numerical "scary room" would be Room 101 from 1984 but presumably here we need 1408 for some reason. ... Some people have told me in comments that there's a scary movie called "Room 1408". I should have googled it :-).

Pocker deck, oh, for pocker deck with 20 more squared with 20 more.

5204: 52 (poker deck) + "oh, for" equals (52+20) squared + 20.

Smaller beast is lone, beheaded within infamous order.

616 (=min(616,666), Revelation) is (-l)ONE inside 66 (Star Wars).

Three rightmost one dropped just a decade from XXth.

This must be 890. I guess 890 = "three rightmost" on a keyboard. Thanks to noedne in comments for pointing out that this is "just a decade from XXth" -> 1890, with "one dropped".

5th Smith holding signed declaration goes down, gradually.

85 (fifth Smith number) containing (17)76: 8-7-6-5 "goes down gradually".

A prime empowered its predcessor, and ate one, too.

81 (a prime empowered: 3 to the power 4) followed by 2 (its predecessor) = "ate, one, too".

Computer science, the one with mixed up weed.

1024 (a power of 2, hence "computer science") = 1 plus an anagram of 420.

Note: squared perfection is perfection.

I guess "note" = 7 but am not sure why; square it and follow it with 6 (a perfect number) to get 496, another perfect number. (noedne in comments suggests 7=note because there are 7 notes in the usual diatonic scale; that hadn't escaped my attention but doesn't really seem like enough reason for "note" to clue the number 7. Might be right, though.)

Credit where due:

thanks to @Somebody and @noedne for pointing out the movie "Room 1408" and to @noedne for figuring out the right way to parse the 890 clue.

• re: around the world clue: rot13(Ebbz 1408 vf n fpnel zbivr.) Apr 30, 2019 at 16:03
• ^ yep, that's the one I referenced. Apr 30, 2019 at 16:05
• Those all seem pretty plausible. Will edit accordingly. Apr 30, 2019 at 16:57