How do you beat the chrysalis on Metal Gear Solid peace walker

When the Chrysalis is in attack mode, use the rocket launcher that target locks. Don't use the Law or Gustav because it won't hit and it's just a waste of ammunition. When he's in normal mode, you can use any type of weapon to take damage to the Chrysalis. What I do is when it flies to me, I use the target lock rocket launcher and get a lock on him. Then, I quickly switch to my other rocket launcher (Gustav) and hit him again quickly as the Chrysalis stops moving when it gets hit in Normal Mode. So I performed a double hit. Always have a pistol, assault rifle, machine gun, or any weapon that's not a rocket launcher and at least 1 rocket launcher when battling the Chrysalis. The rocket launcher is for hitting the chrysalis and the assault rifle, pistol, or machine gun is for hitting the kidnappers that the Chrysalis sometimes launch. I use a double barreled shotgun or an assault rifle. I suggest an assault rifle. I don't use the shotgun much.