Code of Hero - S2-E9
Trivia: In Dinobot's quarters, after thinking about committing suicide, he looks out the window and sees three birds fly past. They're flying the "missing man" formation, which is also performed by Silverbolt, Optimus, and Cheetor at the end of the episode to honor the fallen Dinobot.
Chosen answer: Terrorsaur was probably removed because his character was far overshadowed by Tarantulas. Both characters were treacherous and backstabbing towards Megatron, but it wouldn't have made sense to have two characters who served the same purpose, story-wise. Scorponok was removed because they wanted to introduce Quickstrike, and it wouldn't have made sense to have two scorpion characters on the show.