Prime World centers around a battle between two nations, the Dokht Imperium and the Keepers of Adornia, both of which seek to control Prime, a critical resource. The players' goal is to capture new territory and destroy the enemy's base. Players support their armies in this endeavor by controlling heroes. Each Prime World player is the lord of his or her own castle, which is both their main base of operations and home to the player’s heroes. At the castle, players can build various buildings, from mining facilities to decorative structures. Players can also create new talents and skills which can be chosen later, enhancing the selected hero's assets for upcoming battles.
Prime World combines PvP and PvE session battles in multiplayer online battle arena style with MMORPG-style persistent character progression. Four additional PvP game modes have been released: Dragonwald, with more PvE-oriented gameplay than Borderlands; the fast-paced Outpost with a single lane; defense-based Homeland; and the zombie-ridden Apocalypse. There is also a Shuffle mode, which is similar to Borderlands but with heroes randomly shuffled in a team. It has an optional Facebook Connect mode which allows players to engage with their friends in the game, create teams and enlist their friend's help in various ways.
The game is free-to-play. Won battles are rewarded with experience used to level up and unlock better hero characteristics, and talents. The latter can also be produced at the castle. Each talent can be upgraded up to four times at the cost of other talents. In addition certain talents are specific for a hero and these cannot be upgraded. Each faction has access to over 30 heroes with largely identical gameplay except for the appearance.