Trivia: Masters Storming Ox and Ferocious Croc, and the wolves that are Shen's henchmen all make a brief appearance in the opening of the first Kung Fu Panda.
Kung Fu Panda 2 (2011)
1 trivia entry
Starring: Gary Oldman, Jackie Chan, Angelina Jolie, Jack Black
Continuity mistake: When Po and the Furious Five are in the top floor in Shen's palace, the lights above them are brightly lit. After Mantis smashes the cannon through the floor, the lights turn off.
Shifu: This could be the end of Kung Fu.
Po: But I just got Kung Fu !
Shifu: And now, you must *save* it !
More questions & answers from Kung Fu Panda 2
Answer: Since Po's father was presumably the only panda to attack Shen's wolves head-on, there's a chance Shen could have seen him. Plus in the flashback, Shen orders his wolves to attack Po and his mother before Po's father defends them both with his mallet.