Here's a video of a glitch or a bug in Mega Man X6. The glitch occurs at around 1:45 of the video, so you may want to skip the preceeding video part, if you only want to see what this is about. The rest of the video is included for reference.
Basically, Zero "dies" after he has entered the portal, yelling his death scream. It does not substract your lives, however. I've had it happen to me a couple of times, and it can happen with Zero or X, bosses or no bosses beaten. I have no idea what triggers this, and it may or may not increase your time.
In short, it's an absolutely useless yet curious thing.
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