YMMV / Ben 10/Generator Rex: Heroes United

• Character Rerailment: With the exception of a brief scene referencing Mr. Smoothie, Ben loses most of his silly behavior during this episode to be a more balanced character.
• Crossover Ship: This special naturally made Ben/Rex a popular pairing in both fandoms. The jacket scene and the Fusion Dance between the two don't help.
• Fanfic Fuel: It's explicitly confirmed earlier in the special that Ben got infected with nanites upon arriving in Rex's world, and he is not shown getting rid of them at any point. The concept of Ben returning on his world with nanites inside him and as such the ability to potentially go EVO at some point leaves plenty of possibilities for fanfic writers.
• Like You Would Really Do It: Summed up by Bobo really well.
  "He's gone...to the little ninjas' room."
• Moment of Awesome: Several of them, but the one who gets the cake probably is Ben turning into Upgrade and fusing with Rex to fight Alpha Omega.
• Moral Event Horizon: You can more or less feel sorry for Alpha's situation until he indirectly kills thousands of Evos.
• Nightmare Fuel:
  • Alpha creates his various bodies by absorbing nanites from other Evos, similar to Van Kleiss in the first season. Except instead of being turned to stone, they are reduced to ashes. Now remember that Alpha did this to various Evos over the special, and some of them might have been humans...
  • Go to extreme when he goes to the Bug Jar and absorbs almost every Evo in it.
• They Wasted a Perfectly Good Character: Despite how useful the transformation would have been (not to mention being given ample opportunity to use it), Ben never transforms into Way Big during the movie.
  • Shocksquatch is used for a total of 30 seconds. Ben doesn't bother using him again despite being effective against Alpha.
  • Also, Ben doesn't use any of his Ultimate Forms during the battles.

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