Another oft-revisited idea in comics is doing a time travel story. I will now take the time to analyze the three ways I’ve seen it work.

I’ll start with the easy one. It has been used in various stories. In Crisis on Infinite Earths (COIE), the heroes and Anti-Monitor go to the beginning of time. Their presence reshapes the timestream, merging the realities. In Marvel, Adam Warlock went into the future in order to prevent the Magus from ever existing. Thus, he rewrote the timeline. Hunter/Killer seems to revolve around this notion. This is possibly the most well-known kind of time travel, as it can be seen elsewhere. Doctor Who and Back to the Future come readily to mind.

I don’t like this kind of time travel. It’s largely because of the paradox. If Adam Warlock doesn’t become the Magus because he was killed, then he never has to go to the future in order to kill himself. Of course, the Warlock story sets off other problems, but I won’t get into that here. The other problem I have is that the characters “at the nexus of change” if you will seem to remain unchanged. They don’t gain new memories based on the events they altered. I would actually imagine someone who performed paradoxical time travel to have two sets of memories, much like Clint Barton does post-House of M.

The seemingly most common kind of time travel, if at the very least in Marvel, is when a character goes back in time and causes an alternate reality. This certainly is easier to follow than the previous kind. I can give it that much. One problem is there’s rarely an explanation for it. If they set the machine or whatever they’re using to go back to their past, why didn’t it work that way? My theory is that there’s a force that changes their course. That’s what happened in the post-COIE Legion story that explained the presence of Superboy. The Time Trapper diverted the Legion to a pocket universe he had created.

Another problem with this kind of time travel is that the character accomplishes nothing. Go back in time, try to fix the future, and return to the same thing you left.

And now we come to my favorite. It can be found issue #2 of the current Blade series. in All-Star Superman #6, and in various issues of 52 (culminating in issue #37), just to use more recent examples. This type of time travel is where a character goes into the past and does something, something that history records them already doing. Or, it could be that travel to the future and do something (like meet themself) and later have the same experience, just from the other perspective.

In order to fully understand this kind of time travel, you need to watch Dexter’s Laboratory: Ego Trip, assuming you can find it. I highly recommend it. Why do I like this kind of time travel? Because it needs no explanation. It just is, as if driven by fate.

There is a related kind of time travel, where someone goes into the past and does things that may or may not have actually happened. But that kind is rarely used.