Keir Knight and Yosuke Mino pull off a lot of hilarious facial expressions as the Clown and the Goblin.
Specific episodes
In "Bluebird", after the bird whistle goes missing, the boys have no choice but to watch the Ballerina dance, and the Ballerina practically drags the Goblin over to the steps while Goblin has a look of pure "FML" on his face.
The narrator's comment at the beginning of "Strong Not Strong":
It had not been a good day for the Goblin. He had to glue the precious Toy Castle planter back together. Mostly because he broke it.
"Mary Had a Little Lamb":
The Clown and Goblin's ridiculous swordfight, quickly followed by them pretending to be monsters.
The Goblin reacts to being cast as Mary's lamb with a spectacularThis Is Gonna Suck face.
The Goblin's shimmy-shammy, or shaking his tail in a goofy manner, which he does whenever the China Doll is not looking.
All of "Three Cool Pigs", from the Cool Pigs' dancing to the goofy Big Bad Wolf, to the way the narrator says "Coooooool pigs!".
The completely silly jumping hiccups everyone gets in "Hiccup"; first the Rag Doll, then the Ballerina and Soldier, and finally the Goblin. Every time, they scare each other to get rid of them, which always results in the hiccuper falling right over.
In "Little Red Riding Hood", the Ballerina makes the Goblin be the grandmother in her play of Little Red Riding Hood, which he does not enjoy, as he's Dragged into Drag. He ends up turning Grandma into an Adaptational Badass by fighting the wolf (played by the Clown) himself.
In "Alouette", the Strongman tells the China Doll that anything girls can do, boys can do better. The China Doll shoots the camera a "this guy is full of shit" look.
"Brother John":
When the Soldier and the Goblin play ball by themselves, the Soldier rolls the ball to the Goblin, who is offscreen. After the ball doesn't come back, the Soldier goes over and finds the Goblin fast asleep on top of the ball.
In the Dream Sequence, the Clown shakes some bells like a madman in an attempt to wake Brother John. While he fails, the effort is nonetheless hilarious.
At the end, everyone is so tired, they all decide to take a nap...in a heap, with the Clown sleeping on the floor, the Soldier using the Goblin as a pillow, and the Goblin using the Strongman as a pillow.
In "The Intruder", the Soldier, Goblin, and Clown see a shadow inside their tent (really the Soldier's blunderbuss and hat), and get scared, thinking it's an intruder. They're scared out of their wits, and resort to diving into the tent head-first to fight it off. They all have a big laugh when they realise what's actually in there.
In "The Secret Club", after getting rid of the Clown and the Goblin, the Rag Doll and the Soldier randomly start popping in and out of their clubhouse like meerkats.
