Knight Templar wrote:
there is a special effects scene in "The Doomsday Machine" trailer that does NOT appear in the final episode.
Kirk fires the Constellations phasers at the Planet Killer and instead of the single beam hitting the Planet Killer, we see two beams lance the machine from the opposite angle.
The two phaser beams hitting the machine are NOT the same effects shots used for the two phaser beams from the Enterprise hitting the machine.
You can see it really well on YouTube.
Neither are really in the same vein as the OP's question, but on the topic of scenes which were used in trailers but not broadcast in the actual episode, the trailer of 'Galileo Seven' features an alternative exchange between Kirk and Commissioner Ferris which does not appear anywhere in the episode as transmitted.