* At the end of the last episode of the series before the credits it says "In Memory of DwayneMcDuffie".
** Also, Azmuth giving Ben the new Omnitrix to replace the Ultimatrix;
-->'''Ben:''' But, Azmuth, I thought I proved I was worthy.
-->'''Azmuth:''' As usual, you don't understand. You ''have'' proved your worth. But this inferior copy of my Omnitrix isn't worthy of ''you.''
-->'''Ben:''' But-
-->'''Azmuth:''' OH FOR THE LOVE OF-! ''Look'' at your ''wrist''.
-->'''Ben:''' An Omnitrix?
-->'''Azmuth:''' ''The'' Omnitrix. An improved version I've been working on, ever since you were given the prototype six years ago.
-->'''Ben:''' I don't know how to thank you.
-->'''Azmuth:''' Keep doing the right thing.
-->'''Ben:''' I don't suppose you'd consider giving me the Master Control.
-->'''Azmuth:''' Perhaps for your 18th birthday.
* Charmcaster's Heel Face Turn and friendship with Gwen in "Where the Magic Happens". Especially when she tells the guy who wiped out her magic-using species that "you can't get rid of all of us", referring to her people. And as she says this, she smiles at Gwen and holds her hand, showing that she's accepted her one-time enemy as basically a sort of sister.
* Ben telling Kevin that he's like the older brother that Ben never had growing up.
* This, from "Andreas' Fault", after Argit manipulates the trusting Andreas into a HeroicSacrifice:
-->'''Argit''' (clawing at the ground): Oh no -- I lost everything! Do you know how much money I had in there?
-->''Kevin decks him''
-->'''Kevin''': He trusted you. He loved you, and you used him!
-->'''Argit''': You know, I just don't understand you, Kevin.
-->'''Gwen''': No, you ''don't.''
* Kevin's KirkSummation to Ra'ad in "Fused" -- if for no other reason than it shows how far he's come from the punk he was in the [[{{Ben10}} original series.]]
* In a sick, sad sort of way, Kevin's "Can I have Quarrel back?" in Nor Iron Bars In a Cage to the prison warden was kind of heartwarming. The interaction in the flashback between Quarrel and a newly human-looking Kevin was also incredibly cute.
* Ben kissing Gwen on the forehead before he sacrifices himself in "Ultimate Sacrifice".