Esther is a new unit introduced in Metal Slug Attack.
A young woman from a minority people, she lives in an underworld with a unique ecosystem. Since this peace-loving girl became her clan's representative, conflicts have decreased and negotiations for a co-existence pact have been moving forward bit by bit.
She's able to perceive her surroundings even in darkness. This is due to her ability to sense a light emitted by all living beings, which is enhanced by her special face-mask. The caterpillar that's always with her is her friend, and was born the same day as her.
During the Extra Ops "Glow in the Dark", she and her insect friends fought off an unwelcome Ptolemaic attack, calling Grandee to ram a Deep Sand Marine out of the area.
In the story "False Peace", her clan apparently moved to the surface on a remote island. Allen Platoon heads there to find her, as their main purpose of visiting the island was to recruit her and retake the Huge Hermit. As a result of her powers, she acts as her clan's guardian.
She greets the platoon and orders them to leave, refusing to join their side because she knew they would destroy the village anyways. She also notes Huracan is different and laughs at the thought that she actually joined the Rebel Army to save her village. Since the platoon refuses to leave, she calls in the Huge Hermit, but it is defeated and captured by them. After its defeat, she calls in a swarm of Huge Locusts before disappearing.
- She has much in common with Nausicaä.