Continuity mistake: When Bulgy is driving on the road next to the rails, Thomas can be seen pulling a train instead of being repaired at the foundry.
The Return of Optimus Prime (1) - S3-E29
Continuity mistake: At the end of the episode 'Dark Awakening', Optimus is seen without an eye and an arm, he also has other damaged points, but at the beginning of this episode, when Jessica and Gregory get to Optimus, he is in perfect condition with no damage.
Give Me Your Princess - S1-E17
Continuity mistake: Commander Keith pilots the blue lion for part of this episode since the princess is trying to learn to fly the black lion. When Keith is transported to the lion it is the black lion.