|“||Striker! It's a Category V! The first ever.||„|
|~ Herc Hansen|
The largest and strongest of all the known Kaiju, Slattern is unrivaled by any of its brethren in battle. The creature's high toxicity levels and intelligence makes it the most lethal Kaiju the Pan Pacific Defense Corps has ever faced.
Slattern has thick, leathery skin and three triple-crowned tails that can be used for long distance attacks or piercing the armor of a Jaeger. Its five tails have enough power to rapidly spin and lash out, acting as a mid-range attack, even with a heavy amount of underwater pressure working against them. They were shown to be powerful enough to destroy a Jaeger's oxygen tank.
It also has a spike-like protrusion on its chest, which can extend forward and inflict blunt damage on a Jaeger. The sound of Slattern's roar can emit sound waves that cause visible damage to the environment it is situated in. Slattern's body is extremely resilient against attacks and its impressive size strikes fear into its foes. Slattern's height is estimated at 596 feet and its weight is estimated at 6,750 tons.
Slattern's face is rather unique, with a symmetrical facial structure similar to a hammerhead shark that contains two blue eyes on each side. The Kaiju's chin is slanted. Like Scunner, Trespasser, and Knifehead, its arms are actually fused, ending in three-digit claws.
Slattern emerges from the Breach when the two Jaegers, Striker Eureka and Gipsy Danger, approach the rift itself in a mission to collapse it with a thermonuclear bomb. Just as Striker Eureka gets to the edge of the Breach, Slattern appears, and quickly overpowers Striker by attacking the Jaeger with its multiple tails, sending it flying into a wall, and badly damaging it.
As Striker Eureka recovers from the hit, Slattern leaps on the Jaeger and tackles it, using the rocky surroundings to cause further damage. However, as the two giants continue to battle, Striker gains the upper hand on Slattern, creating a slash across the Kaiju's throat and wounding it in the chest with its arm blades. When Slattern realizes that its losing, it calls out to Scunner for assistance. As Slattern and Scunner begin to converge on Striker for the killing blow, its two pilots, however, Stacker Pentacost and Chuck Hansen, decide to detonate their nuclear payload in order to clear a way for Gipsy to enter the breach and destroy it (as Gipsy Danger is powered by a nuclear reactor, and this could serve as a substitute bomb). The resulting nuclear explosion kills Scunner and destroys Striker Eureka, killing its pilots. However, Slattern miraculously survives, though severely wounded.
Just as Gipsy is about to make the leap into the breach, Slattern returns, blocking the Jaegar's path. With no way around Slattern, Gipsy leaps foward and tackles the massive Kaiju, sending them both falling into the abyss. On the way down, Slattern uses its tails to stab Gipsy's back, which damages its air supply. But before Slattern can cause any further harm, one of Gipsy's pilots, Raleigh, fires the nuclear turbine that burns a hole straight through Slattern's chest and through its back, finally killing it. Gipsy Danger is then able to use Slattern's corpse to pass through the Breach successfully and detonate its nuclear payload, destroying the portal and also killing at least 3 of the Precursors, if there are any left.
- Guillermo Del Toro has cited Chernabog from Fantasia as an inspiration for Slattern's appearance scene.
- Slattern is the largest, strongest, and presumably the most cunning kaiju in Pacific Rim, having designed that way by its creators to combat the returned Gipsy Danger.
- Both Slattern and Otachi, in the film, are almost dragon-like in feature.