she will come back

Willow starts a little basic--a bit of onscreen text (that is entirely superfluous) about a prophecy involving a baby that will grow up to bring down Queen Bavmorda (Jean Marsh).

(The plot is a little like The Lord of the Rings except it's a baby instead of a ring, and Gandalf is an old woman who was cursed into the shape of a possum.)

Nurse gets the baby out of the dungeon (though the mother is killed) and manages to get the baby as far as a river, where she pulls a a Moses allusion sending the baby on her way. The nurse, like the baby's mother, is also killed. The baby is Elora Danan and it occurred to me just an hour or so before turning the film on tonight that this story has a lot of female energy to its cast, despite its leads being Warwick Davis as the titular Willow and Val Kilmer as Madmartigan.

In the opening scene, we've already passed the Bechdel test, and we probably don't realize it just yet but we have also passed the Mako Mori test. The main plot may be Willow's, but it is driven by 1) saving Elora Danan, 2) on the behalf of Cherlindrea (Maria Holvoe), 3) with the help of Fin Raziel (Patricia Hayes), and 4) eventually with the help of Sorsha (Joanne Whalley).

Back in 1988, I don't think I would have even noticed the gender balance in the film. Willow's quest begins as a very male-heavy quest. Meegosh (David Steinberg), Vohnkar (Phil Fondacaro), Burglekutt (Mark Northover) and at least two others (Tony Cox and Malcolm Dixon), and of course, it is the High Aldwin (Billy Barty) who sends them to give the baby to the first human they see.

(I remember in the novelization, each of these Nelwyn "warriors" has their own backstory told along the way.)

At first. Once they find Madmartigan, they all abandon the quest but for Willow. He continues on with Madmartigan. And, to be fair, these two will be joined by brownies Rool (Kevin Pollak) and Franjean (Rick Overton), and in the big battles later in the film, Airk's (Gavan O'Herlihy) presence will matter, but none of these characters have their own storylines. Cherlindrea sends Willow to get Fin Raziel. Cherlindrea sends Rool and Franjean along with him. The obvious central story is Willow proving himself capable by taking Elora to safety and even facing off against Bavmorda (alongside Fin Raziel, of course). But, watching the film again after many years, I am trying to focus on the female characters.

(By the way, I've never read the followup series of novels written by Chris Claremont, but they take place about 15 years after the events of the film and teenage Elora is the main character.)

 
 
 
 
 
Cassandra Bausman, in "Conflicted Hybridity: Negotiating the Warrior Princess Archetype in Willow", explains

While women worried are a familiar presence in fiction, and television screens have been graced with strong heroines since Xena took her place as a small-screen queen--

And, certainly well before Xena, I would point out. From Wonder Woman to the Bionic Woman, for two examples.

--there is a comparative lack of such characters in fantasy film. In most such films, women have often played central roles, but those roles have frequently reinforced gender stereotypes, remained two-dimensional, and been supporting rather than leading. More broadly, women have historically played very limited roles, often restricted to evil (or good) queens and/or sorceresses, beautiful princesses and/or love interests, saucy and buxom wenches or barmaids, or mythical creatures like fairy queens...

As Bausman points out, all of these types exist in Willow, but I would contend that the sorcerer Nelwyn, the self-professed "greatest swordsman", and a couple comic-relief brownies are hardly normal male character types, strictly speaking. Well, Madmartigan is. But, he spends a good part of the film in pink pants (fashioned from a dress he wore to pose as a woman before his reunion with WIllow), and Kilmer fuels him with a chaotic energy that one would never expect in, say, Aragorn in The Lord of the Rings. Willow and Madmartigan get the most screentime, but their stories are beholden to the women around them. And, the women all have some sort of power, whether magical, political, or both. Even the nurse's defiance in taking Elora away was powerful.

But Bausman continues:

The warrior princess or "chick in chain mail" is comparatively rare.
However, the classic fantasy adventure film Willow (1988) manages to feature all of these character types... Bob Dolman, the screenwriter chosen to fix [George] Lucas' story to the page, has confessed to just such an agenda, admitting that he "was secretly trying to get more women into the movie and attempting to make it different from all other movies George had done." The injection of female roles is notable, with the role of eccentric magical teacher (Yoda) and evil ruler (Emperor Palpatine) both made women...

I guess by this metaphor, Cherlindrea is Obi-Wan Kenobi, and Kiaya (Julie Peters), Mims (Dawn Downing) and Ranon Mark Vande Brake) are lucky they didn't meet a fate like Owen and Beru Lars.
But, back to Bausman:

...and, while there is a feisty Princess paralleling the Leia role in Sorsha, the struggle between good and evil, the choice between her mother's rule and the cause of a band of freedom fighters which echoes Luke Skywalker's epic journey, is also, ostensibly, made hers. Indeed, Princess Sorsha, Willow's dominant female character, is an important character in the history of screen heroines, as she, as a sort of archetypal hybrid, represented--

Represents, present tense.

--a kind of heroine not often seen and yet remains one of the most nuanced examples of a warrior princess in a fantasy film.

Bausman goes on to argue,

[in a] tale of unconventional heroes uniting to fight for what's right... [Sorsha's] character arc, by virtue of a liberalized conversion from antagonist to protagonist, is arguably the most transformative and significant in the film, perhaps best explicating the themes of the film as a whole.

Sorsha's choice to join Madmartigan and Willow against her mother is pivotal to their quest going the direction it goes. Without her, they wouldn't have survived the fight at Tir Asleen. As Bausman points out, after that fight, Sorsha's role becomes far less important, more a tagalong to Madmartigan than her own person. But, in terms of decisions, actions, that affect the outcome of the plot, hers accomplishes more even than Madmartigan initially taking Elora from Willow at the crossroads, because he rather quickly loses the baby to the brownies whereas Sorsha remains a central force in the final conflict against her mother's forces. Bausman suggests,

...in allowing the character to be so easily read in this limited way [as following Madmartigan], the film trades complexity in for type, evolution for tradition, and, in so doing, skirts the need to explore the motivation and consequences of her decision, thus reducing Sorsha's role in the final third of the film--

It's more like a quarter, but still problematic.

-- to a somewhat awkward accessory rather than a primary agent in the coming final battle. This [sic], we find the flagrant erasure of a female character and her experiences and motivations.

Like the chaotic energy of Kilmer's Madmartigan, I would argue that Whalley infuses enough energy in her role as Sorsha that even pushed aside in terms of action, her presence ahead of the army at the gates of Nockmaar.

Bausman cites earlier material associated with the film, and Sorsha's increased role there, for example, after "joining the rebels, she pursues and defeats a number of enemy soldiers on horseback with a superb demonstration of bother her skills as a warrior and her new allegiances, [but] the film does not [provide this scene]."

Effectively, Sorsha's final overt act (aside from simply being part of the mass attack later) is to kiss Madmartigan. Her princess role over her warrior role. Bausman argues,

once Sorsha joins the other heroes, the film no longer needs her to b a warrior, it has other characters, traditional male characters, who fulfill that function, rendering her suddenly secondary rather than necessary in that capacity.. As careful as the film seemed to be in initially establishing a respect for her identity as a warrior, it's final scenes grant Sorsha little to do.

Except it is Sorsha who kills Bavmorda’s seers, clearing the way for Raziel.