is there a way to pass this level without shoting?
Unfortunately, since they are all armored enemies, you have to at least get off one shot. You can then grab the hit enemy, throw it at another enemy and repeat the process until finished. It would be possible to do this gun-less if you could become invisible at the beginning of the level (but even by spamming the E and R keys I couldn't force this thing, in the web version at least), at which point you would simply kick a random enemy instead of shooting him and then complete the level as described above. A bit of a shame because I managed to complete all the other levels without shooting!