I think I have the solution ... do I have to submit a demo?
Click here to view the secret text
×You enter the room with your sword positioned to face SW. You will use this position to strike the orbs, making sure there are no roaches to face in the top section of the level (above the roach queens' positions). After luring the roach queens out to the SE corner of the room, you attack each roach with your sword positioned to face SE. This is done by rotating the sword 90 degrees from its SW position. You defeat each roach, one by one. Defeating roaches as you progress to the SE corner, kill the last few roaches that the queens have newly spawned, then proceed to kill the roach queens.
Not that hard.