Monday, 16 June 2025

bakpao

No hybrid today, we're doing a variant of Pentominous instead!

I found this ruleset browsing through past Japanese championships, where it has appeared as a variation on Tetrominous. I tried setting that at first, but Tetrominous and I really don't get along and I either kept ending up with no solutions or a not-very-GAPP solve path. Using pentominoes instead worked out great though!

The puzzle's name in the tournament I found it in just translated to Tetromino Division which is a bit too generic of a name, so I'm going with Pentominous (Border Clues) instead.

Rules: Divide the grid into regions of five orthogonally connected cells so that no two regions of the same shape share an edge, counting rotations and reflections as the same. Clued cells must belong to a region with the pentomino shape associated with that letter. Borders must separate two different regions. A clue on a border indicates that pentomino must appear on one side of the border.

Interface note: Answer check is set up for edges (default), lines or letters. If using letters, be sure to fill every cell with a capital letter. If using lines, make sure you draw a full square for the 2x2 part of a P pentomino (see example solution).

Acquire a Speedy Sloth 🦥 by solving in 3:00 or less!
Obtain a Quick Crab 🦀 by solving in 6:00 or less!
All solvers who complete the puzzle will be rewarded with a Delayed Drongo 🐦!

Example (Penpa+): https://tinyurl.com/2cnowpn4
Main (Penpa+): https://tinyurl.com/29kw66dp