I thought Rolling Shield was the only thing that even hurts Third Form Sigma. Call me crazy, but I'm pretty sure that's how it was in the original Mega Man X. I believe they changed it in Maverick Hunter so the X-Buster also harmed him, but I distinctly remember only Rolling Shield harming Sigma's Third Form in the original game.
Rolling Shield is Sigma's weakness. It deals 2 damage. To hurt him with the buster, you must fully charge it to the max. The max as in after getting the Arm Upgrade. You're forced to get the Arm Upgrade (Zero gives it to you if you don't already have it) because of final boss Sigma only being harmed by that (and Rolling Shield but that's just a weakness :P)
I would have beaten Sigma long ago if I used Rolling Shield but nah :P
Oh okay. I don't think I ever bothered trying a fully charged X-Buster shot on Sigma. I guess I just figured "well, none of these other weapons are working, so I just have to use the Rolling Shield."
Either way, I'm typically the type to actually use the boss's weaknesses whenever possible anyway and only just using the Buster to test myself. lol
Man, that must've been difficult to pull off. I remember Sigma inflicting a lot of damage when with a full life bar. Typically have to use a Energy Tank or 2 to defeat him.
_________________ The Local Video Gaming Lunatic
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