While walking to get a signal, Arcee fell behind Optimus.
Optimus saw and helped Arcee to her feet, to which Arcee suggested that they should take a drive to Miami but Optimus stated they would use up energy.
This made Arcee sorrow over her partner's tragic death and left her scarred in her mind.
Cliffjumper even tried to comfort Arcee by stating he knew Tailgate's death (even when he and Bumblebee was there to save Arcee right after Tailgate was killed by Airachnid) and understood why Arcee decided to be a loner.
After her talk, Arcee started to feel even more sadden over Cliffjumper's death.
Miko rests her hand on Arcee's hand as they watched the sunset, which comforted Arcee.
In Predacons rising, Optimus mentioned Cliffjumper's noble sacrifice and Arcee mourned over Cliffjumper. Even though Optimus is a lot taller than Arcee, she's his best fighter, his go to gal whenever he needs someone to talk with.