You know I just remembered, back when the first Sentinel Prime pictures showed up and we all thought that he'll be helping Optimus my dad also saw them on my computer and said "Who's that the new badguy from the Transformers?" and i responded "No he's an Autobot, he's actually Optimus Prime's mentor and Optimus looks up to him!" to which he said "...." "Bullshit that's totally a bad guy!" And few month later we see that he really is a double crosser. My dad was right all along!