Scunner's appearance and behavior is akin to that of a bull. Broad and stocky, its two curved horns jutting out of its head act as battering rams against armored opponents like the Jaegers. Scunner possess four arms that aid in its ability to move faster than its opponents underwater.
Its plated body armor allows it to take great amounts of damage in the most severe environments. Like most Kaiju, it has a green bioluminous glow throughout its body. Its ability to work in tandem with other Kaiju makes it a particularly dangerous foe in combat.
When Scunner and Raiju emerged from the Breach, they waited for the arrival of the two remaining Jaegers, Gipsy Danger and Striker Eureka. Upon their approach to the Breach, Scunner and Raiju circle the Jaegers, using their lack of visibility against them. Once they reveal themselves, Scunner engages Gipsy Danger in combat.
Gipsy Danger subdues Scunner, but before Gipsy Danger can kill Scunner with its right-arm GD6 Chain Sword, Raiju's jaws clamp down onto Gipsy's arm while swimming at top speed, tearing its arm off.
Scunner frees itself from Gipsy's hold and takes advantage of the damaged and disorientated Jaeger to bite and cripple Gipsy's right leg. Unleashing its chain sword from its left arm, Gipsy pierces Scunner through the neck and drags its head over a volcanic pit, burning its face. Scunner, thrashing from the pain, escapes and off balances the damaged Jaeger, giving it time to recover. Raiju attacks Gipsy Danger a second time, but is cut in half by its chain sword.
Striker Eureka's endurance against Slattern forces the Category V Kaiju to call for aid. Scunner abandons its fight with Gipsy Danger in order to attack Striker Eureka. Gipsy's crippled leg prevented the Jaeger from helping Striker in time. As Scunner and Slattern move in to destroy Striker Eureka, its pilots detonate the thermonuclear bomb on its back, killing Scunner and critically wounding Slattern.
- Scunner uses the same basic CG body as Knifehead and Trespasser in Pacific Rim.
- Scunner is the largest Category IV in Pacific Rim.
- Scunner and Raiju are the last Category IV Kaiju to emerge from the Breach before its destruction.
- The word "scunner" is Scottish. "Scunner" refers to something that triggers a strong reaction of disgust.
- Scunner is featured in Pacific Rim: The Video Game and Pacific Rim: The Mobile Game.
- Scunner is depicted on the Blu-Ray release of Pacific Rim, replacing Gipsy Danger in a lenticular image.
- NECA's Pacific Rim action figure series includes a deluxe figure for Scunner, released around August of 2014.