When the Star Wolf team comes in, press start around the time Leon makes the comment, about six seconds, for best results, and also to get the lead on the enemy. When one of them is about to turn to avoid one of the columns with Andross's face on it, shoot them like crazy. If you do it right, they won't be able to move out of the way and instantly crash into the pillar and die, regardless of how much life they have. This is the easy (and quick) way to get the medal in Venom, and you can have single lasers and still pull it off.