Zero-K is a freemulti-platformopen sourcereal-time strategy video game. Initially based on content from Total Annihilation on the open source Spring Engine, it was forked and all proprietary content replaced, and evolved into a completely new game with unique features. Among the games powered by the Spring Engine, Zero-K makes extensive use of Lua scripting for interface and gameplay changes/enhancements, as well as unique real-time strategy concepts such as a flattechnology tree.
Gameplay
Zero-K has similar gameplay to Total Annihilation and its successor, Supreme Commander. As computers grow faster, Zero-K intends to scale with them, allowing players to increase their resolution and allowing for higher unit counts with virtually no limit. Players start out with a construction-capable bipedal mech known as the Commander which acts as the player's avatar. Players use their commander to construct a base of operations from which they can expand to fight and ultimately destroy opposing players. Players can upgrade their commander with new weapons and modules as the game progresses. The game includes 10+ factories each with 8+ unique units for a huge variation of viable build orders on most maps. Aside from the factories, there are many important buildings that create resources, provide radar coverage, shield units from Enemy weapons, conceal units from enemies, provide defence to a static location, and perform many other functions. In Zero-K any player can create any unit through the appropriate factory. The initial construction cost of a factory is the only investment needed to gain access to its units. There is no technology progression during a game. Each unit's reason for being used or built is its appropriateness for the battle at hand, not devoting resources to gain access to it. Economy in Zero-K, like in Total Annihilation, consists of two resources, Metal and Energy. Energy is produced by certain structures, most of which can be built anywhere; each of these structures is ideal for its own set of situations. Energy is consumed in all build projects 1:1 with metal, for repairs to damaged units and structures, during "Resurrection" of unit wrecks, powering structures like radar towers and charging shields, and is used to activate the biggest defenses such as the "Annihilator" energy weapon. Metal is either extracted from metal in the map using "Metal Extractors" or reclaimed from wrecks and debris of destroyed units and structures. Each and every unit or structure requires a specific amount of metal to be built, making capturing areas suitable for metal extraction or reclaiming wrecks of utmost importance in every game. Connecting energy production to Metal Extractors allows "Overdrive", automatically producing additional metal. However, Overdrive has diminishing results, requiring more and more energy to continue increasing the production bonus until additional attached energy has only negligible increases in production. There exists a single player campaign where players start with only their commander and a few basic units. Each mission unlocks a few more units to slowly introduce the player to the game. The missions do not have to be played in a fixed order so that the player can choose which units to unlock first. Depending on the player's performance, each mission yields a different amount of experience points. The player can use these experience points to improve their commander. Zero-K minimizes the amount of interface limitations. Executing sophisticated strategies is made as simple as possible, including queuing up any number of units, ordering a constructor to build many of different buildings, or ordering a factory to build planes that would automatically patrol a route as they roll off the assembly line. The interface allows players to build up large armies and bases with ease so the player is free to concentrate on actual tactics and strategy. Zero-K is almost unique in having this level of control.
Online play
Zero-K can be played online in 1v1, team, or free for all style battles, as well as playing cooperatively against Chickens, bots or in the campaign. Planet Wars is an massively multiplayer online style strategy game tied to Zero-K where individual battles are fought against other players to gain "influence" on planets. Each player can either create or join a clan, and all the influence they earn will count toward the clan's. Planet Wars resets each time one clan achieves one or more of the three victory conditions - Conquest, Economy, Technology. However, ever since season 8, a new faction system has been implemented: Each clan and player is randomly assigned to a faction, and all the influence that person or clan makes will count toward the faction's.
Chickens
Zero-K includes a unique game mode called Chickens. Chicken games are essentially similar to tower defense games, except the player is free to build any units. The chickens will adapt to the player's strategies, deploying siege weaponry and special units if the player plays too defensively and deploying heavier defenses against offensive players. Chickens comes in various levels of difficulty, as well as the ability to set custom difficulty options. In a game of Chickens, the goal is to survive an onslaught of various semi-sentient alien creatures until their "Queen" attacks. The objective of a game of chickens is to survive, with a side objective being to destroy "Roosts" placed around the map - keeping the attacking chickens from becoming more powerful. The game ends with either annihilation of the players, or the death of the Chicken Queen.
