I really like the concept between Super Time Force. Essentially, if you guys don’t already know, you’ll select one character, and play as them until they die. Once they die, you’d go back to the start of the level, and select a different character, but your old character will still be there, and perform the actions you did in a past life. I was confused on how I’d make the aspect of having a dead character performing actions performed in the past, because it’s done so smoothly in this game, and I can’t think of any efficient way of doing it.
I don’t think this is the right place to post such a question, you should post specific questions about Unity here. What you want is to basically design a game mechanic system. This can be a really complex topic.
I don’t know how the system in Super Time Force works, maybe you can find an explanation somewhere else.
I try to give my thoughts on the mechanics:
Basically, you somehow have to record the movement of the character you played and replay it on that character in the next run. The easiest way could be to record your input and apply it the same way on the character. The character is then controlled by the replay data. For this to really consistently work, you would have to have a fixed framerate and it would be necessary that the world behaves the same (platforms, enemies, whatever). Else there could be undesired outcomes. But regardless how you do it, you may want to have your game/characters designed in a way, so that the characters do not only accept user input, but also the input you recorded. Maybe make some sort of interface that takes either the recorded input or the player input and then sends the same commands to the player (recorded “attack” action would be the same as the player pressing attack on the keyboard). Your record data have to have some sort of time stamp. I recommend the ingame time. While replaying, when the current ingame time exceeds the time when the action was recorded, apply that action to the replayed character.
Another possibilty could be that you record the transform (position, rotation, etc.) of your character, when which animation was activated and when an action was set, such as attacking, etc. which has an impact on the environment.