Pretty much everything Kaos says. His Deadpan Snarker sidekick makes it even funnier.
Kaos: My head is awesome, I tell you! Fear it! Fear my GIANT FLOATING HEAD!
Kaos: Impossible! You survived my best water spell! Ahem! I MEAN... You survived a very mediocre water spell that I found laying around - somewhere.
Kaos: Attention! Here is the list of Skylanders that I want to be caught and disposed of immediately. Ahem. ALL OF THEM!
Skylanders: Giants gives us Drill-X, a drill robot that is the boss of Chapter 11, who starts rapping about how he's going to destroy you.
The SWAP Force commercial has several funny moments. Observe.
The Wii U version of Trap Team has the villain displayed on the game pad. Poking them will make them either roar or lash out at you. The same goes for the Skylanders when the villain is in control, but they only have one reaction (their "defeated" animations) after several pokes per character: Snap Shot will throw his weapons to the ground and turn away from you, arms crossed in a "Hmph!" fashion, characters like Spry and Blades will get upset and look dejected, looking at you sadly (Blades' comes complete with his lower lip quivering) and Pop Fizz in normal form will start hitting himself in the head with an empty potion bottle, to name a few.
Flynn being scared by Tessa at the start of the Pheonix Psanctuary level in Trap Team.