The Criminals are minor antagonists in the Kung Fu Panda franchise. They serve as the opening antagonists of the 2008 film Kung Fu Panda (appearing in a dream by Po), and the main antagonists of two segments of Secrets of the Furious Five.
Very little can be said about the personalities of the multiple, imaginary crooks in the first film, or most of the bandits that Viper's father defeats in Secrets of the Furious Five. They seem to have no real standards, as they rob from some bunnies and threaten Po before he even challenges them.
The Wool Stealing Crocodile Bandits are greedy and ruthless, but at least have the decency to feed their prisoners and show shock when they believe they are dead.
The Gorilla Bandit that breaks the fangs of Viper's father is a cruel brute, who brutalizes the elderly snake after breaking his fangs. He also isn't very bright, as he underestimates Viper when she tries to save her father.
Kung Fu Panda
Before he became the Dragon Warrior, Po had a dream about defeating a gang that consisted of hundreds of criminals. He encountered these villains as they were stealing from innocent bunnies. One criminal (an Ox) challenged Po, who quickly disposed of him and almost all of his allies (even blinding a clouded leopard and a crocodile with his "awesomeness"). Po, of course, woke up, and these criminals ceased to exist.
Secrets of the Furious Five
A gang of crocodiles appeared in Mantis's segment. They were stealing wool when Master Mantis challenged them. Mantis was not aware of their habit of setting traps, and was captured by the crocodiles. They mock him, and make him their prisoner. Several days later, one crocodile goes to feed Mantis, but is outsmarted by the insect, who pretends to be dead. The crocodiles open the cage, and Mantis jumps up and attacks them, defeating the villains.
In Viper's segment, gorilla bandits (and a mid-sized crocodile) were shown being defeated by Viper's father, who then threatens a whole group of villains. One day, a Gorilla Bandit attacks the village and challenges him. The elderly snake's fangs break on the gorilla's poison-proof armour, and the brute begins to toy with him. Then, the young Viper herself arrives. The gorilla is amused by her small size, but she starts ties him up with ribbons. He tries to crush her, but she is too fast for him and so he is completely helpless and tied up.