This is a
Fillomino
puzzle where every polyomino is required to be an L-shape, as in
Sashigane.
Write a number in every empty cell so that every group of cells with the
same number that is connected through its edges is an L-shape (with arms
of positive length and 1-cell thickness) with that number of cells.
My second, and now symmetric, attempt at this crazy self-invented
mutant; puzzle 22 was the first.
A word of warning: I can’t solve this without bifurcating near the end,
so logic purists may be disappointed, but I like the clue arrangement
too much. In fact I suspect this puzzle could have many more clues
removed without affecting uniqueness, so tight are the rule constraints
in this type.
This is a
Fillomino
puzzle where every polyomino is required to be an L-shape, as in
Sashigane.
Write a number in every empty cell so that every group of cells with the
same number that is connected through its edges is an L-shape (with arms
of positive length and 1-cell thickness) with that number of cells.
May be slightly reminiscent of
no-rectangle
Fillominoes. Slightly… (Has anybody done this before? It
seems so interesting that I feel like I couldn’t be first.)

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.
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.]