The Search for Alpha Trion

The scene in which Optimus Prime connects to Elita One with a long tube and then produces suggestive sounds has become infamous among fans for its unintended yet amusing sexual undertones.

As Starscream brags about how he managed to capture Prime, the animation of the scene is completely missing. Optimus should be hanging down from a rope above a pool of acid, yet the pool and its contents are missing, thus the bubbles and smoke seemingly rise up from nothing. Also, both the bubbles and the smoke are unmoving.