Counterpunch wrote:No no no...
Sentinel got hit like, 3 times and had his hat knocked off. He shot friends in the back.
Megatron just 10 seconds earlier betrayed his greatest partnership.
In a good dojo, students are taught that "Dead tigers are the ones that kill you." Meaning that it's the battles you assume you've won that are easily lost. Good for Prime to finish what had to be done.
I'm not debating whether they deserved to die (they did). I'm saying that when Optimus them, they were no longer threats: Megatron was definitely not going to kill Optimus. He had the opportunity to let Optimus die, and he chose to save him. He then had the opportunity to kill an injured Optimus, and chose not to. Plus, his army was utterly defeated and the grand scheme had failed.
Similarly, Sentinel was beaten to the point he couldn't even get up. Optimus had time to have a ridiculous conversation with Megatron, kill him, get Megatron's gun and then exchange a few words with Sentinel...by which point Sentinel could still barely prop himself up with his arms. He was not a threat.
The point is, this was a movie; it's generally fine to kill the villains, but very rarely are they in a situation like Megatron or Sentinel. I can't think of another scenario where the bad guy saves the hero, offers a truce and is brutally killed anyway (by the 'hero' supposedly being a through-and-through good guy).