Rangers of Two Worlds: Part II - S1-E47
Factual error: The climax of the episode features the Aquitain and Zeo Rangers fighting together, in Angel Grove. However, they are actually fighting outside the Tokyo Dome, in Japan. Further proof: http://www.rangergallery.com/albums/userpics/10012/Zeo%2520Rangers%2520and%2520Alien%2520Rangers.jpg.
Answer: Instrument of Destruction.
The question was how was Skull able to keep his fear in check when the Cogs came to get him. Not what episode it happened in.