Bastet is a free open-source terminal Tetris clone that deliberately gives you the worst piece. See how it works, features, and where to get it.
Bastet, short for 'bastard tetris', is a free, open-source, terminal-based falling-block puzzle game created by Federico Poloni. It plays like a classic Tetris clone but with one deliberate twist: the game does not select your next piece randomly.
Instead, Bastet uses a scoring algorithm designed to hand the player the least helpful piece available for their current board layout, intentionally working against the player rather than for them, which is the source of both its name and its reputation for being 'evil'.
The game runs in a terminal using the ncurses library, keeping it lightweight and dependency-free, and it is widely packaged across Linux distributions as a small, self-contained retro-style game.
The centerpiece of Bastet is its adversarial block-selection algorithm, which evaluates the current board and deliberately picks the piece least likely to help the player clear lines, rather than choosing randomly like standard Tetris implementations.
Bastet offers two difficulty modes: a normal mode that still shows a preview of the upcoming piece, and a harder mode that hides the preview entirely, with the selection algorithm further tuned to take advantage of the player not knowing what is coming next.
According to its own version history, the algorithm has been revised more than once, including a rewrite in version 0.43 that added logic to avoid repeating the same piece too many times in a row, keeping the adversarial pattern from becoming too obviously predictable.
Bastet is completely free and released under the GNU General Public License version 3 (GPLv3), with no paid version, in-app purchases, or subscription of any kind.
As open-source software, its full C++ source code is publicly available on GitHub, allowing anyone to inspect, modify, compile, or redistribute it under the terms of the GPL.
It is available through the package managers of most major Linux distributions, so most users can install it with a single package-manager command at no cost.
Bastet stands for 'bastard tetris', reflecting the game's design goal of deliberately giving the player the worst possible piece.
Yes. Bastet is completely free and open source, released under the GNU General Public License version 3 (GPLv3).
Instead of choosing the next piece randomly, Bastet uses a scoring algorithm that evaluates the board and deliberately selects the piece least likely to help the player clear lines.
Bastet was created by Federico Poloni, and its source code is maintained in the fph/bastet repository on GitHub.
Bastet is primarily built for Linux and Unix terminals using the ncurses library, and it is packaged in most major Linux distributions; ncurses-compatible builds exist for other Unix-like systems as well.
Yes. It has a normal mode with a next-piece preview and a harder mode that hides the preview, with the piece-selection algorithm adjusted accordingly.
Bastet is an independent, unofficial falling-block puzzle game inspired by Tetris-style gameplay; it is not an officially licensed Tetris product.
Bastet can typically be installed via a Linux distribution's package manager, or built from source from its GitHub repository at fph/bastet.