Swamped

Ash holds up two of them, then holds them together and lets go of one. The two coins stay together.

"They stick to each other. Might be magic, might be lodestones. Don't know enough about either to say for sure which it is. Maybe something happens if you stick a bunch together..."

Ash's voice trails off and he looks down at the box.

"They're starting to come together on their own," he says, backing away and dropping the pair in his hand. "This might be a good time to get your weapon out."

You pull out your mudpike and watch. The box bursts open suddenly, and... well, something that looks like a giant metal spider comes out. But it doesn't do much of anything afterwards - it just sits there.

Now what?