From the campaign:
Retrocausality is a rules-light tabletop game about time travel, in the vein of Bill & Ted's Excellent Adventure or Back to the Future. It's designed for quick play, with a simple card-based system and loose travel rules.
The original Retrocausality was released in 2013. Retrocausality 1st Edition will be an upgraded version, with professional layout and commissioned interior art. Backers get immediate access to the original version!
In Retrocausality, you play time travelers. You can tell stories about adventurous scientists, lucky kids, time cops, aliens, or whatever else you can imagine, having adventures through time and space and hopefully correcting all the damage they accidentally do to the timeline along the way.
The action is fast and simple, making it ideal for starter games, pickup games, and conventions. The core mechanic is the Timeline: a series of index cards prepared by the Game Master, representing important events the players are mucking around with.
Changes you make alter the Timeline, causing new index cards to be added or replacing previous cards. If you undo something later, simply put the index cards back where they were.
The Kickstarter has made it over their funding goal, but there's only 4 days left to get in on the action.