Rising Tide has been announced as the first expansion pack for Firaxis Games' Sid Meier's Civilization: Beyond Earth. It will release in Fall 2015 on PC, with Aspyr being in charge of the Mac and Linux ports, for $29.99.
Rising Tide has a slew of notable additions. It will allow players to build floating settlements, which I interpret to mean water-based cities, and extract new resources that can mined from deep within the planet. Given all of the resistant alien sea life, though, this might be easier said than done.
Diplomacy will be given an upgrade as well (thank the stars!), with players being able to enhance traits, making relationships between other players more pronounced, and "leveraging the benefits of your allies." By investing in multiple affinities, you can unlock hybrid Affinity units and upgrades.
You can also choose to belong to one of four new factions, like Al Falah, "a group of nomad explorers descended from wealth and resilient Middle Eastern states." Along the way, the new Artifact System will allow you to collect alien artifacts around the planet for powerful passive bonuses.
Firaxis and 2K will reveal more about Rising Tide at E3, but you can watch Firaxis' livestream at 11am PST/2pm EST for more information.