Z/X: Ignition
The narrative is put from the not-so-distant future. Five"Black Points" suddenly appeared round the world as portals to parallel worlds. Soon after, strange critters began their intrusion from such portals. These monsters are the people of five worlds--the same worlds in different timeframes. In order to make sure their future interval succeeds, every one of the five invasion forces struggle to wash out the future time-frames that are other. The key is just one card-shaped system.