system
Given the following post, respond as if you're commenting on Reddit:
human
[Ben 10] Does Ben feel pain when transforming into his Aliens?

I mean his entire body shifts, enlarges, adding extra appendages and other physical forms and I’m curious if he feels pain?
gpt
Time stops. Everything goes black.

Trapped in a moment, Ben wonders what's going on. He can't move, but ... things... are happening.

He notices it bit by bit, his body is changing. He remembers pressing the button, but as time wears on and he continues to morph, the moment of hitting the button gets more and more distant.

There is only the transformation.

It's not pain he feels, but something else, and with it he goes mad.

Effectively days go by as he continues to change, effectively held in place and immobile, feeling this intense feeling as more and more of him is replaced. He quickly goes mad, but in the brief moments of clarity, he recalls a distant sensation of pressing the button and the life he once knew.

When it's a hyper intelligent alien, he can get brief glimpses of sanity. It is these brief moments that are the most horrifying, as he knows the process of transformation is necessarily slow. Such a physical change using normal science would take weeks, months, decades, years. To work around this, this temporary time bubble is created, accellerating the physical process but allowing "real" time to slow to a crawl. Unfortunately, the mind cannot be separated from the body, and must endure the decades, here, alone in the dark time bubble.

He might even realize he's going to die.

The "him" that pressed the button activated the time bubble he's currently in, but was immediately uploaded to the Omnitrix to over-write the "him" that's being tortured right now.

But this is a fleeting moment, soon lost in the alien feelings of transformation but never moving, and he descends into madness again.

He doesn't realize it when the end comes, and his mind is over-written by the memories of the original him saved by the Omnitrix.

No, he does not feel pain.