Cuckoo Condor is the boss of the Ruby Passage in Wario Land 4. Initially it that resembles a mechanical monster vaguely resembling an old-fashioned cuckoo clock. Cuckoo Condor attacks via a claw which can be used to damage the machine by swinging it back making it hit itself.
After taking enough damage the machine is destroyed, revealing a deformed vulture-like creature that floats around laying eggs that hatch into exploding chicks. Wario defeats the bird by catching the eggs and throwing them back onto it's head. Once defeated Cuckoo Condor explodes in a cloud of smoke much like the other bosses.you cant see me