I made this a long time ago but put it off until I had programmed
enough to digitize it without my fingers leaving the home row. I think
the finish is interesting.
LITS -
Nikoli. Exactly one tetromino per region, no 2x2s, they’re
connected, adjacent tetrominoes are noncongruent.

Yeah, I lied last time I made one of these; the original Nikoli name
wasn’t that hard to remember, and “sashigane puzzles” has shown up as a
search query, so here you go. Perfect opposite-type-clue rotational
symmetry, chaotic_iak! I hope you’re satisfied now.
I have just realized that I have only ever tried one level of
difficulty in puzzle construction, viz., “as hard as I can make it”.
This is mainly because I don’t want to construct anything overly trivial
with the same few tricks, but, well, maybe it’s not the best idea for
actually trying to build an audience.
Am I actually trying to build an audience? Am I? *shudders*
(Yajilin summary: fill in some cells, draw a loop through the rest,
filled cells aren’t adjacent, arrows denote # of filled cells along some
ray; MellowMelon’s
rules)
Corral puzzle, aka Cave aka Bag etc. (Yes, from nikoli.) Short rules:
draw a loop along the grid lines; each numbered cell is in the loop and
the number denotes how many cells can be seen vertically or horizontally
from that cell, plus the cell itself. Stealing link to
MellowMelon’s long
rules.
Slitherlink with 20 clues taken out as dominoes and their original
positions shaded. For more lucid rules please visit
MellowMelon’s
puzzle 263.
Domino set is all possible dominoes exactly once each:
{00,01,02,03,11,12,13,22,23,33}
A bonus gift for the birthday of a very important person! Ignore the
colors while solving.
Just a normal one this time.
Somewhat depressing almost-symmetry.
If you are reading this, then our APMO testing time is over! There’s
a small chance of me being really happy or really frustrated about how I
did, but I’m betting on a solid “meh.”
Rules
page by mathgrant. There’s no way I’m going to memorize the Japanese
name yet. [edit: It’s Sashigane. It’s not that hard.]
A ratio-preserving enlargement of the janko.at sample invocation
puzzle, perhaps. I wanted to try using smaller clues. Finally a grid too
large for full-size displaying! Is that even supposed to be an
achievement?