Powered by an AAA 1,5 V battery, this circuit works on an oscillator made with the on/off behavior of the pnp~npn transistors combined with the capacitor in feedback. The big value inductor coil pourpose is to make the magnetic energy trapped in itself collapse through the parallel diodes that, in a second moment (inductor discharge) share an huge current spike (0,1 Amps), while the transistor are "off".
Like the pulses that modulates the leds are something like random and irregular i used a normally closed button, to make initially start the pulses.