Episode 4 lowlights:
1. Everyone thinks Goblin Slayer-san is going to kill a prisoner but instead he kills a goblin in the room no one else could tell was there. Then he goes "idk what y'all were thinking; I'm here to kill goblins." (In the first episode he killed a wounded adventurer.)
2. When they finally get to the underground goblin lair they wait until the goblins start to wake up, then cast a sleep spell on all of them, then massacre them for a few minutes while they sleep.
3. The boss of the lair isn't a goblin. Slayer has never heard of its species before because he's a massive bumpkin. ("Oh... so you're not a goblin?" -Slayer)
4. Slayer has to pop some potions to finish the fight and he does it with his back turned to keep up the "this guy eats and drinks with his helmet on" sight gag.
5. Weaponized town portal scrolls.
spoiler (click to show/hide)
"Goblins?! You would use this to kill mere goblins?"
"Goblins... are far more troublesome than you."