I remember coming up with a plan for 4D gameplay for MK before. It could definately work.
Imagine a 3D game is released now that has all characters that have been around since before MK4.
They fight in a realm where time is unstable and everybody has the ability to cause bubbles of time differences.
You would be able to make an area of the stage a different time frame and when characters enter that area, they either revert back to a younger appearance or take on an older appearance.
For instance, say there was a character like Sub Zero and the older he got the more powerful is ice attacks were, but maybe his physical attacks grew weaker. Maybe with a character like Scorpion you could revert back far enough to be human.
But the effects are limited to the area that is created during the match by a player.
My other take on it was creating areas where time moves differently, like an area could be slowed down or sped up.
Also, for all of them, the idea of the characters aging noticeably as they are used appealed to me. So when you play, you pick a character to stick with and as you use that character he or she ages along the way, with chi-attacks gaining in energy but maybe something else changing.
I think something fun could be done with 4D for a fighting game. But, I don't actually believe any developers would do anything cool with it. They'd do something gimmicky and stupid and we would all end up hating it.
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