A while back I saw a comic that NECESSARILY consisted of an odd page and an even page, i.e. a single sheet (printed on both sides). The peculiar thing was that it showed three or four armed characters at what looked like a wall, seen head-on in the panels, with shots coming out of it and shots being fired at it. The twist is that the ones being shot at were themselves, firing from the other side of the wall. One of them dies fairly early, maybe from his own shot, and I think none are left at the end.
It's from the 1990s at the latest, and not the late 1990s. There are three or four characters, with a bit of a sci-fi feel because of the weapons they carried. One dies early and his companions say something like "what bastards!" ("qué cabrones"). I think they all die at the end from the bursts of fire they hit themselves with from the other side (I vaguely remember they fire those bursts after their companion's death). I saw it in an adult (underground) comics magazine published in Spain.