His simple physical explanation can be countered with an equally simple psychological observation.

Everyone, move to the flank!

The numbers on the outside doors were a hint.

Why did you open an outer door?

We're looking for something motivational that would help us.

As for our flank...

They are attempting to flank the enemy.

I'll attack from the side and defeat them.

It looks like they're hitting our outer walls with small missiles.

Continue switching and prepare to target the flank!

Everyone else, attack its flanks!

She avoided the surge by running on the side of the vehicle!

Team Zero will provide cover from behind Team One.

Oh, they're back. From my flank.

Wrong! On the side!

The tatami floors are on the sides now! The room’s been flipped!

You've chosen an outside door, I see.

Second, to open one of the outer doors.

The displays on the outer doors are changing here, too.

There's a new map stuck on the side.