He doesn't swim naked, so he takes the summon anyway.
Once he's close enough to get a good look at what they're shooting at him with he shreds it, interpolating it with air.
On the other side is... a very recently-abandoned industrial complex of some kind, situated in an open field under an unnervingly low sky. If he cares to look, it's reasonably obvious how the aliens were constructing their ships here to be passed through the portal in pieces and then assembled on the other side. The portal itself was extremely well-guarded until just now, but there are no aliens left.
Cam takes to the air, takes pictures, disintegrates industrial complex bits, and looks for where the aliens may have scurried off to.
Luckily, Cam can fly, and the lack of anything else whatsoever makes it really easy to spot the two other portals available. Presumably the aliens went through one of those.
Of course someone does! That's promising. Cam hauls the rest of the way through, takes a few pictures, disintegrates weapons.
Cam wonders if they're made of Real Physics or Actual Substances, but doesn't let this wondering distract him too much from indirectly blowing shit up. These aliens are really fond of their self-destruct mechanisms.
Cam is going to need to make a map. He starts a map. He goes back and sticks his head through the other fork out of Ex-Industrial-Park.
Do these aliens want to talk if he makes a speaker and yells at them?
How many portals out of here?
He thinks he's cleared enough of a buffer zone to go back and notify the clam planet people though.
He makes a new comm. "Hey there!"
"Hi! So the aliens really, really don't want to talk. They want to shoot ineffectually at me and then blow themselves up. A lot. There's a maze of spheres past the next one - it forks into two, and then one side's got five and one's got six, haven't gone farther than that yet. Do you have anything resembling a guess of how long it would take me to convince all these aliens to self-destruct?"
"That's likely to depend on how many there are, and we've never been able to determine that beyond 'always more'," says Azair.