Diana triggers it

{If Tyra’s dispel magic uses left:=0}”You got no more Dispel castings left, there’s nothing we can do but go through and take it,”{else}”We can’t waste your Dispel castings,”{endif} Diana says sullenly, before slipping past Tyra and tip toeing in between the plinths, perhaps hoping in vain she might escape the trap’s tender mercies by walking very softly.

As soon as she passes in between, the orbs glow brighter for a moment, and there is a thrum of energy in the air. Initially it appears that nothing happens - had she carried her longsword through it would’ve transmuted into water in her grip, but ironically the sword got saved by the mage hand carrying it past. However this does not apply to the other metallic item on her person: her belt buckle. A splash of water stains her trousers, running down her legs to the floor. The glow of the orbs subsides.

More taken by surprise than horrified, Diana spins around to face Tyra, pointing at the puddle of water that used to be the buckle: ”What the fuck kind of weird magic..”

Before Tyra can say anything in response, Diana’s pants slide down, and slip halfway down her legs, revealing her khaki panties. With a blush and an awkward fumbling, she pulls them back up as fast she can. Without a buckle to hold her belt tight, her pants are as slack as if wearing a potatoesack.