Self-destruction lever with a timer and alarm.

Script
function selfDestructionWithTimer(selfDestructionTimer) {
  const time = new Date().getTime() + (selfDestructionTimer * 1000);
  function selfDestruction() {
    const now = new Date().getTime();
    if (now >= time) {
      alert("boom");
    } else {
      setTimeout(selfDestruction, time - now)
    }
  }
  selfDestruction()
}