When a mysterious alien being arrives on planet Skyla, the planet's inhabitants tried to make peace with it. However, its intentions were anything but... destroying all in its wake and forcing the planet's inhabitants to flee as none of their weapons could even harm it. Study revealed that the alien was able to exist in two different times simultaneously, and could only be harmed in both. A special time machine was built - one that can transport someone into the past and the present at the same time...
Chronos Twin is a side-scrolling platform game with a difference - the action takes place on both Nintendo DS screens simultaneously. The top screen shows the player in the present, while the touch screen shows the player in the past. Pressing the A Button will make both the past and present player jump simultaneously. While there are certain differences in the past and the present (for example, a platform in the past may not exist in the present), as long as the player is standing on the platform in one time period, they won't fall.
The player also has a weapon at their disposal - a gun which can be fired in the present with the X Button, and the past with the B Button. However - the gun cannot be fired in both time periods simultaneously. The gun can also be charged up by holding down the button, releasing a more powerful blast.
After a certain point in the game, the player is also able to stop time in one period while moving about freely in another period. This can be used to move blocks to allow both present and past players to get through, or to release platforms that a player in one time period couldn't reach.