Alex jumps forward a bit, then turns to fire arrows in Mallory's attacker's back.

She drops and rolls away.

Lianne's barely noticing the others' fights; she swings, aiming to cut off her attacker's arm, while Sophie's halberd develops a cross-beam like a boar spear as she angles for her familiar to impale itself. 

Mallory escapes, and five-arms stumbles forward, growling its rage, catching itself on its one good leg and two arms before it collapses.  Arrows strike its torso, and it screams, hobbling toward Alex like a gorilla.

Lianne's sword gets halfway through her familiar's arm, and then it's stuck in the bone.  Its legs thrash, and it begins to slide down the blade towards her.

Sophie's familiar impales itself, its tiny ineffectual arms grasping desperately at the air, trying and failing to reach her.

The scream continues.  It sounds more like a rant, now, though they can't make out any words.

Mallory raises herself into a kneeling position, summons a high-powered riffle, braces herself, and shoots five-arms in the back as many times as she can, while Alex skips backwards some. 

Yeah Sophie's halberd can develop spikes, how about that. 

Lianne lets go of her sword, has an idea, screams "Down!" and then summons the largest sword that'll fit in the room, backing into the center and spinning as hard as she can, aiming so her own familiar will be hit last. The other girls all hit the floor, Sophie immediately summoning a second spear and stabbing up at whichever nearest familiar remains standing.

There is a great deal of flying ex-familiar ceramic.  It may hit someone.  Lianne, for example, in the arm.

Screamed invective continues, impossible volume balanced by impossible distance.

There is a rhythmic, high, chaotic sound, getting steadily closer.  Shattering glass, perhaps.

Lianne shakes her head a bit, heals herself, and glances to make sure that the familiars are all dead and no one else is injured (they can heal themselves, but still).

Familiars are dead.

Healing herself is unpleasant.  The shard seems to twist and writhe as the regrowing flesh pushes it out.  It skitters a bit when it hits the ground, but then falls still.

No one else is injured.  But the sound of rhythmic shattering glass is getting closer, and suspended clouds of glass still block their way.

"Wait here until we know what it's doing?"

The others nod. Lianne tries experimentally to push aside some of the suspended glass with her (now more reasonably sized) sword.

She succeeds; the shards stay put when nothing's touching them, but the sword can move them just fine.

Crash.

Crash.

Crash.

Crash crash crash crash - 

Every pane of glass around them, floor to invisibly distant ceiling, shatters, every piece rockets through the air towards a whirling cyclone of shards.  Protrusions like arms or tentacles extend, slowly, curling and grasping through the air towards them.

(It is crystal clear to Lianne's magic senses that this phenomenon is not the witch.)

Multiple kinds of familiar, okay then.

They move to surround it, Sophie stabbing at its center, Lianne going to cut off its arm-tentacles, Alex and Mallory firing up into it.

Ha ha ha, nope.

...Is it slow enough they can just run past it.

Well, past it, in the direction it came, is away from the center.  But if they're really fast about opening the cabinet doors they can probably keep ahead of it and still be heading in the right direction.

Lianne bats at it with the flat of her sword, aiming to push some of the shards away from it, shouts "Run for the center, it'll vanish when we kill the witch!" She waits until the others have gone in the right direction, continually trying to disrupt the whirlwind, and then goes out last.

Glass panels shatter around them, or as they leave a chamber.  The cyclone matches their speed, shards of glass shrieking against each other, screaming a storm of indistinct invective.

A few of the chambers have familiars in them, lumbering things with two heads or one eye, or tiny top-heavy creatures whose torsos are just enormous upward-facing jaws.  Some of them lunge toward Lianne and the others as they pass, but they all seem just as afraid of the cyclone as they are: they're fleeing in mad terror, stumbling and swaying clumsily.  Glass tendrils descend on them and shred them to bits as the cyclone passes.

And then, eventually, the next cabinet they reach is locked.  The cyclone is only a few rooms behind, and gaining rapidly.

Sophie, Mal, and Lianne all drop barriers as they run (Sophie can form her spears into umbrella-like things, which she props behind her; Lianne starts turning her swords into shield-like things sized for each door; Mal can form actual shimmering magical barriers, that should slow down the main bulk of the cyclone). 

Mal shoots out the glass of the next cabinet, and Lianne immediately bats aside any hovering shards with her sword. 

Much good may it do them.

The shards aren't suspended in midair, this time, they shoot right for the cyclone.  The shattered glass provokes renewed, more vicious shrieking and ranting.

The hail of glass is not kind to exposed skin.

They're magical girls, they can heal (Lianne's healing noticeably faster and easier than the others, now that they're all injured at once). 

They jump into the next room, weapons ready.

It's not fun.  The glass twists inside their flesh, trying to resist being pushed out.

The next room has five sides, all at right angles to each other, which is disorienting.  The path to the center is still straight(?) away from the cyclone.

She's starting to get used to this. 

They head for the center.

More locked doors, more shattered glass, more painful healing.  Five- and six- and seven-sided square rooms give way to crosshatched hallways, with ordinary wood-backed glass cabinets like the ones in the entrance room.  Familiars stumble and stagger through the hallways, occasionally colliding with a wall of glass and shattering it, provoking more furious screeching.

They're getting close, and with no doors in the way, they can put more distance between themselves and the cyclone.

Every so often, they notice an especially huge familiar with a glass display case embedded in its chest, cradling some vase or sculpture or jewel in red velvet.

She's really glad they all topped off their soul gems before coming out here.