Firaxis has offered up details on Indonesia and Khmer, its two new Civilization 6 factions due to release later this year.
Khmer, led by King Jayavarman VII, last appeared in Civilization 4 and brings with it a range of unique benefits, including Jayavarman's Monasteries of the King leader ability. This enables holy sites to grab adjacent territory and provide food and housing when built on a river. Khmer's Grand Barays ability, meanwhile, grants farms the power to produce additional food when adjacent to an aqueduct, and for aqueducts to provide faith and an amenity.
Khmer can also access the Prasat unique building, which replaces the temple. Missionaries produced here gain the martyr promotion, and it provides a Relic Great Work slot.
Khmer's real show-stopper, however, is its unique unit, the Domrey. This is a siege unit in the form of a ballista mounted on the back of an elephant; it's stronger than a catapult, can move and shoot on the same turn, and can exert zone of control. Yes, that's right: you'll get to manipulate murder elephants.
If none of that appeals, your other new option is Indonesia, led by Majapahit warrior queen Dyah Gitarja. Indonesia's unique ability, Great Nusantara, allows coastal tiles to provide minor adjacency bonuses for holy sites, campuses, industrial zones, and theatre squares. Entertainment complexes, meanwhile, give an extra amenity if they're adjacent to a non-lake coastal tile. Indonesia has a definite watery theme.
And continuing that theme, Indonesia's unique improvement is the Kampung, which provides housing production and food for each adjacent fishing boat when one is built on a coastal tile next to a water resource. Its unique unit is the Jong, which replaces the frigate. The Jong is a fast vessel that enables all units to match its speed when in formation. Additionally, a Jong gains extra combat power in a formation.
Wrapping things up for Indonesia is Gitarja's leader ability, Exalted Goddess of the Three Worlds. This enables naval units to be purchased at discount using faith, and allows religious units to embark or disembark without any movement cost. Additionally, coastal cities receive bonus faith. Given Indonesia's general watery theme, it should come as no surprise to hear that it excels at establishing strong cities on smaller landmasses, where many other factions would struggle to settle.
Both factions will be available at no extra cost if you already own Civilization 6's Digital Deluxe Edition, or they can be purchased separately on release. Firaxis hasn't yet specified a launch date for Indonesia and Khmer, but it seems likely that they'll arrive alongside Civ 6's major new autumn update, due soon.