Seismograph — free browser game

Seismograph puts you at an observation station: a waveform is drawn on the screen and you have to assign it to one of five categories — Earthquake, Blast, Truck, Whale, Wind. Every event has three phases. First the trace phase: the wave is written left-to-right as if on paper; watch its shape carefully. Then the answer phase: the drawing stops, a countdown bar drains along the bottom and you have a short window to call it — press 1-5 or tap a button. Finally the reveal phase: the correct label appears as a badge over the wave, the right button flashes green and your wrong pick (if any) flashes red. A correct answer scores 10 base points plus a streak bonus (+2 per consecutive correct, capped at +15); a wrong answer or a timeout costs you one life and resets the streak. Lose all three lives and the run ends with your score stored locally. Every five events you advance a round: the wave is drawn faster and the answer window shrinks — your reflexes get squeezed. Tip: an earthquake carries a small foreshock (P-wave) followed by a longer main shock (S-wave); a blast is a single sharp spike then near-silence; a truck is a soft but sustained low-frequency rumble; a whale is a clean slow sine song; wind is structureless chaotic noise. Press R at any time to restart; your best score is saved in the browser.