Lianne dodges, overshoots a bit, corrects, then makes her sword really big and swings at its center (Sophie jumps back a bit, but not before a parting swipe). 

After it's cut in half, it shatters violently like a dropped vase.  Green and black shards fly through the air, narrowly missing Lianne and the other girls.

Eep!

...Is it dead-dead? (She stays ready just in case, remembering Mallory's words of caution earlier).

It seems to be.  The shards, once they hit the ground, are inert.

Yeah but is the maze fading like last time, can she still sense a witch? Or was that a familiar?

No such luck.  Seems it was only a familiar.

Yeesh. Well, luckily there's the team, and it was fairly easy.

They continue on towards the witch, keeping an eye on the shards until they're past them.

Shards remain inert.

The cabinets continue to admit visitors to pass through them.  The chambers get bigger.  The path to the witch winds nonsensically, turning right or left without warning, sometimes doubling back.

Then, after some time, they come upon a room in which all four paths, including back the way they came, lead to chambers with familiars in them.

If the familiars aren't reacting yet, the girls move to stand back-to-back, then each points at one of the familiars, picking their targets. Mallory then summons eight large machine guns, two per familiar, and fires them in a short burst, additionally shooting her main pistol at her chosen target, while Alex fires as many arrows as she can (three at a time, every other second), and Lianne and Sophie both ready their weapons and brace themselves, Sophie preparing to spear the familiar on a charge, Lianne preparing to swing.

Bullets pierce the panes of glass, and they shatter into minute shards that billow out in clouds and then ease to a stop, suspended in midair.  Vases and sculptures explode, opaque fragments of glass and ceramic fly like shrapnel.  There is a high distant scream of inarticulate rage.

The familiars, irregular assemblages of limbs and heads and mouths, roar and charge through the clouds of suspended glass without fear or hesitation.

Alex's goes down quickly; Mallory's, the largest, charges forward heedless of the bullets, bounding forward on one-and-a-half legs, readying its five arms to grab her in a bear-hug.

Lianne's familiar is just an enormous three-elbowed arm emerging from a pair of legs, big enough to crush her head in its fist.  It staggers forward, half running and half falling, graceless but purposeful.

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.