From a purely fluff standpoint, might something more technological be more suitable for the 'whistle' ability? Something like 'ping' akin to modern day ping commands which would send out a signal intentionally alerting other robots in the area to its location.
The whistle is actually a really freaky robot noise, which is funny when you pair it with "whistle." The game plays up a lot of humor in parts, so the idea of a whistling robot is as funny to me as a robot called "BlunderBot" which says "Oops!" as it fries its friends on the first shot.
There's a mix of being thematic and dark and being funny. The levels themselves can be creepy, and the ambient noises in the background are definitely unsettling (and can be turned off or down if you don't like that). In retrospect I guess it has kind of a similar mix of tone of something vaguely like Portal -- vaguely
vaguely -- though in general I'm not comfortable at all with that comparison. Our writing isn't nearly as funny and isn't trying to be, and the games are nothing alike in general at all. But the mix of funny plus thematic is similar in some very vague respects. Mainly I bring that up because Portal shows that it can be done, versus really to say that our game is anything like Portal. Can you tell I don't like comparing my stuff to Portal?