Personally, I'm not a fan of prologues. When I had to make one for my own comic it drove me INSANE. I hated the idea that we needed one at all, so I did a smart/stupid thing and made the prologue into a story in of itself. It's a 22 page action sequence. I used it as a means of showing the reader what the world looks like, what the main character will be facing, setting up the stakes, and giving a view of the technology and teamwork that will be expected later down the line.
Those first 22 pages were the first comic work I EVER did. Looking back I think I could have stripped that down substantially, but hindsight is 20/20. >_>;;
The good news is that our readers love it that way. They like getting thrown into the action head first, and loved that there wasn't any narration, and we trusted them enough to figure it out on their own. That's something that I find a lot of creators seem to forget. They don't trust their readers. In school I learned the 1st rule of visual storytelling is, "your audience is stupid." I find that idea to be demeaning to the reader. It does make MY job harder, but it makes the readers appreciate and enjoy the comic more.
Why spell out everything through narration? Why not do something different and let that information unfold through your story? You can set up rules, expectations and ideas through your characters and how they interact with their world. It's harder for sure - that exposition dump is a real thing you gotta find creative ways to work around, but if it's done right it makes more a MUCH more satisfying read.
I'm with @shazzbaa, if it's straight up narration keep it short and only touch on the bare minimum. Let the details come out in the story, or even better, let some of the details be disputed. Maybe one character believes and says, "You guys, this is totally what went down!" While another character may say, "Surely not! My educated opinion says it happened this way." So when you actually find out the real story along the way it reveals more about your characters and how they could both be wrong, or both be right in their own way!
I hope that was helpful? :o