Croaker is a period-2oscillator component consisting of six rotor cells in the shape of a toad, with three of them being alive in each generation. Unlike the similar flutter, it cannot be supported exclusively by stator cells. However, it can be seen in oscillators such as Lei, in which two of them are supported by two R-shaped components. Certain phoenix oscillators also contain croakers, stabilized by flutters and/or other croakers.
