Gumball: YOU'RE NOT MY BROTHER! YOU'RE JUST A FISH, WHO GREW LEGS!!! Announcer: ULTRA COMBO!!!!
Gumball defeating the evil virus in "The Virus". After it has them cornered after possessing cars and trying to run them down, Gumball challenges it to come and get him by appealing to its ego. After the virus emerges, Gumball simply steps on him. It's even more impressive because Gumball actually won by being smart for once. The anticlimax of it also makes is a Crowning Moment of Funny.
Richard gets one in "The Hero" for rescuing Gumball and Darwin from the car crusher in the junkyard.
In "The Limit" after Richard was tricked into being a man and demands Nicole do as he says, Nicole responds by giving him a Death Glare so deadly, it blows away all the stock on the store shelves.
At the end of "The Castle", Nicole forces the people who trashed her house into cleaning up and leaving by using a Penance Stare.
The song "Make The Most Of It" from "The Kids" counts as two, as it not only shows how awesome your childhood can be, but is also a great send-off to Gumball and Darwin's original voice actors (Logan Grove and Kwesi Boakye).
In "The Void": Gumball, Darwin, Molly and Mr Small escaped from the void via Janice, a van that ramps through a closing while shooting out rainbows.
As completely, stupidly unnecessary as it was for Gumball to take one of Darwin's super-sneezes just to prove he wasn't going to leave him, you have to admit it's pretty impressive that he managed to hang on during the whole thing.
Nicole saving Darwin and Gumball in "The Mothers" from falling off a building by using a hose to swing after them.
Gumball calling out Penny's father for making her feel bad about her new look after she runs to the woods in "The Shell."
To make it even more awesome, Mr. Fitzgerald immediately admits to being wrong, then Gumball tells him not to beat himself up about it.
Gumball dropping his usual idiocy, laziness, and cowardice to help Penny, including having himself launched into the air to catch up to Penny quickly realizing that he had to be cruel to her to make her small enough to avoid having them be hit by a truck.
Even Mr. Fitzgerald get his when he makes up for what he said to Penny by slamming his car into the Pest Control's truck to protect his daughter from getting shot and trusting Gumball to get to her.
Hell, the episode should be called how Gumball became a man! He came a long way from Season 1 where he was a loser protagonist who had no talent and very shy to Penny back then. Now in Season 3, he showed determination that would make his mother proud by showing how much he loves Penny's true form by going through the burden in coming for her and showed his true love as they kissed. He even got Penny's father to approve their relationship! The kid's not so much of a loser now huh?
Nicole citing "Survival of the fittest" and taking out Mr. Small and the other members of the apocalyptic gang (who were about to eat them) in "The Pizza."
Gumball, Darwin, and Anais taking out the police officers surrounding their house with Home Alone-style booby traps in "The Friend."