In development. Free Russian-language browser puzzle; no signup or download. Guide two lights through different mazes with one shared command. Cross-world switches, ice and fragile bridges; 16 introductory levels, endless mazes and a shared UTC daily challenge. Official website: https://echo.alchemist-safe.ru/ . The playable link is our published HTML5 build on itch.io and supports embedding. AI-assisted development.
Use arrows/WASD or on-screen direction buttons. Bring both characters to their portals simultaneously. A wall stops only one character. Plates open matching doors in the other world; ice extends a step; a fragile bridge disappears after leaving it. Undo and hints are available. Interface: Russian. Progress stays in the local browser.
Echo — Эхо was submitted to SlowDen by AlchemistSafeRU. SlowDen did not make this game - it is published here from the developer's own submission, added on 2026-10-26. It runs in the browser with no download, no install and no sign-up.