Zero-K technically has "space" combat. This is true of any game where units can end up high in the sky, and where being very high up has any mechanical meaning. In our case, extreme height makes units immune to weapon fire from below. Even missiles with cylindrical range have a fuel limit that gives them a maximum reach. As a result, advances in space travel tend to be patched out, which is notable because we generally err on the side of keeping creative special tactics in the game. But over time, the "Zero-K cannot into space" rule has emerged as a result of space travel being so non-interactive. Viewing space alongside the ground also causes interface issues. Complete Annihilation saw our only fully intentional foray into space. This was the original Owl, a spy satellite (probably) added by CarRepairer. [quote]This stealthy orb can serve as a spotter for your artillery or spy on an opponent's base. It uses a lot of energy to stay in the air but is safe from nearly all units. Vulnerable to advanced fighter planes and long range missile towers.[/quote]It flew 5x higher than the highest aircraft (Nimbus), moved slower than the slowest ground unit (Jugglenaut), and had a tiny 300 elmo sight range. It cost 300 metal at a Core Gunship Plant and, as per the description, could only be shot down by the heaviest ground-based anti-air and air superiority fighters. In other words, this unit only interacted with Artemis and the missile-based Raptor equivalent of the day.
Owl did not last, and became the namesake of the term "To Owl" something. It was nerfed to the point of uselessness because the main balance designers didn't have the heart to remove it, but could see how troublesome it would be if it were at all common. If the enemy had a Plane Factory, then it is just dead, but without access to planes it required very expensive anti-air to dislodge. The hard-counters were too hard and too expensive, while there were zero soft counters. So it was soft-removed, and did not survive the transition to Zero-K. The reception of Owl set the pattern of subsequent space exploration, and the lack of direct support fostered creativity. People would have to repurpose units to achieve their space dreams, with the main culprits being the gravity shenanigans of Newton, Lobster, and Placeholder. Each of these units has been patched to curtail space travel, although Newton has received the most attention, as the oldest of the three.
Newton is a turret that uses gravity guns to attract or repel targets. Units are allowed to aim and fire at anything, provided there is some reason they would want to, so Newton can target allied units. People quickly realised that Newtons could fire units across the map, with terraformed ramps to help aim and angle the shots. These Newton Cannons were the first form of "space" travel, yet they still exist today, which seems at odds with the injunctions above. What makes the current uses of Newton "legitimate", and what else had to be patched out? Space is a problem when it dominates entire parts of the game, with little or no counterplay. Newton cannons sometimes win games, but they are hardly a source of cheap, unblockable, death from above. Most Newton cannons launch jumpjet units, but these can be seen as they float down, and shot down in the sky or intercepted. It is a fine back-pocket strategy, but can be countered without too much more investment than it costs. It is also quite important that the units barely go to space, i.e., they can be seen at a comfortable zoom level. The worst cases of space travel let units fly so high that the map is merely a tiny square in the distance.
The first dominant Newton cannon strategy was due to Skuttle, which is a troublesome unit that can cloak, jump, and explode for massive damage. The first issue (mentioned last year) was that it used to be able to jump from space to float down, cloaked, onto the enemy base. The only theoretical counter was to hover gunships above everything important, and station overwhelming firepower nearby to kill the Skuttle in the brief proximity decloak window. So we invented jumplegs to stop Skuttle jumping while mid-air. But this did not stop people raining cloaked death from above. The next issue with Skuttle turned out to be a broader issue with gunships. A gunship can be pushed by Newtons, but cannot crash, which makes it great for safe space travel. A transport with a Skuttle could be shot high into the sky, beyond the range of anti-air, and flown over the enemy base. Then the Skuttle could be dropped onto important targets below, cloaking on the way down. This prompted a few changes. The first was a general nerf to gravity guns such that only 25% of the vertical component of their force applies to gunships. The second was a targeted nerf for transports, namely that they accelerate downwards towards their desired height faster (a buff in any other situation), and they give units a small random push when dropped, to remove the precision of orbital drops.
Gunships can cause issues without the help of Skuttle. After high-flying gunships were blocked, people began experimenting with horizontal "space". Newton cannons can be designed to shoot gunships sideways off the map, beyond the range of ground anti-air. This let transports and Krows sneak around to the back of the enemy base without having to penetrate front line defenses. The tactic has far more counterplay than orbital Skuttle, but by this point out-of-bounds tactics were established as an exception to the usual protection of creativity. So we put a stop to gunship slingshots by pushing aircraft back into the map, with a buffer zone of 400 elmos, which is approximately the turning circle of the most cumbersome aircraft. Planes could be launched off the map too, and the buffer even had to be halved with the more recent addition of Odin. Another borderline, yet still ultimately removed, tactic was the Flea launcher. Fleas are cheap and very light, which makes them cheap to launch with a basic Newton cannon. The issue here was that sight ranges are cylindrical, or 2D, by default, which made Flea launchers dominate other lategame scouting options. We were happy with the spread and effectiveness of other, more nuanced, forms of scouting, so the Flea launcher was nerfed. The nerf involved dynamically reducing the sight range of launched units, to approximate a form of 3D sight range (the actual shape is a cone twice as high as the sight range). Players are still free to scout by shooting Fleas at fast, low, trajectories, but this requires a much more expensive Newton cannon.
What of Lobster and Placeholder? Both units used to be able to create self-powering floating space stations, arbitrarily high in the sky. Lobster achieved this by continually firing a large enough clump of Lobsters, since it used to be able to shoot while mid-air. Placeholder can target allies, and tends to lift its target slightly above the ground. Enough Placeholders can form a self-sustaining clump that gradually drifts upwards. The major issue here is that disappearing into the sky makes defeat almost impossible, and Zero-K prides itself on having a better draw situation than Chess. Sky bases are also good places to give ballistic weapons a height advantage, although this is a cool ability, provided it does not become unreasonable. Space Lobstervator and Placestation were removed on the same day, shortly after Lobster's defeat-avoiding ability was showcased. The fix in both cases was to make the abilities of Placeholder and Lobster decay with height. Lobster cannot boost anything more than 400 elmos above the height of the target terrain, and since then lost the ability to fire while mid-air. A Placeholder shot exploding more than 1200 elmos above the ground has no effect. This happens to be the altitude of the old Owl, although the ramp down to 1200 means that in practice the mass will float around 1000 elmos up. So units can still be maintained quite high in the sky, just not arbitrarily high.
The last, and silliest, way to go to space is due to Dirtbag. The idea is as follows: Dirtbags drop a bit of terrain when they die, so why not stack 500 or so on a single position, then detonate them? The result is a very thin, very tall, spike. This became a problem when people figured out how to glitch Crabs up this spike, which let them shoot at absurd ranges due to their ballistic trajectory. This sort of thing is a neat creative way to create instant spires for Crabs, but the spires could be so high that the rest of the map becomes a few distant pixels. We patched this out by limiting the steepness of terrain created by Dirtbags. Such spires are now limited to 800 elmos, which is still significant, but do not turn Crabs into full-map artillery. That is it for ways to go to space, apart from simple bugs, such as a bug that let players store impulse and release it all at once. That is also about it for creative tactics that have been patched out, since by and large we try to keep them in, with Newton cannons being a prime example. Space is the main exception, since it is too far removed from the terrain and interactions that make Zero-K great. The same can be said of underground units, but since that was only an ability for one chicken, I would not expect an article on mobile burrowing any time soon. Index of Cold Takes

• Traditional real time strategy with physically simulated units and projectiles.
  
• 100+ varied units with abilities including terrain manipulation, cloaking and jumpjets.
  
• 70+ mission galaxy-spanning campaign to be enjoyed solo or co-op with friends.
  
• Challenging, (non-cheating) skirmish AI and survival mode.
  
• Multiplayer 1v1 - 16v16, FFA, coop. ladders, replays, spectators and tournaments.
  
• PlanetWars - A multiplayer online campaign planned to start in May.
  
• Really free, no paid advantages, no unfair multiplayer.

Fully Utilized Physics

• Use small nimble units to dodge slow moving projectiles.
  
• Hide behind hills that block weapon fire, line of sight and radar.
  
• Toss units across the map with gravity guns.
  
• Transport a battleship to a hilltop - for greater views and gun range.

Manipulate the Terrain

• Wreck the battlefield with craters that bog down enemy tanks.
  
• Dig canals to bring your navy inland for a submarine-in-a-desert strike.
  
• Build ramps, bridges, entire fortress if you wish.
  
• Burn your portrait into continental crust using the planetary energy chisel.

Singleplayer Campaign and Challenging AI

• Explore the galaxy and discover technologies in our singleplayer campaign.
  
• Face a challenging AI that is neither brain-dead nor a clairvoyant cheater.
  
• Have some coop fun with friends, surviving waves of chicken-monsters.
  
• Cloaking? Resurrection? Tough choices customizing your commander.

Casual and Competitive Multiplayer

• Enjoying epic scale combat? Join our 16v16 team battles!
  
• Looking for a common goal? Fight AIs or waves of chicken-monsters.
  
• Prefer dancing on a razor's edge? Play 1v1 in ladder and tournaments.
  
• Comebacks, betrayals, emotions always running high in FFA.
  
• Want to fight for a bigger cause? Join PlanetWars, a competitive online campaign with web-game strategic elements, diplomacy and backstabbing (currently on hiatus pending an overhaul).

Power to the People

• Do what you want. No limits to camera, queue or level of control.
  
• Paint a shape, any shape, and units will move to assume your formation.
  
• Construction priorities let your builders work more efficiently.
  
• Don't want to be tied down managing every unit movement? Order units to smartly kite, strafe or zig zag bullets.

Plenty of Stuff to Explore (and Explode)

• Learn to use all of our 100+ units and play on hundreds of maps.
  
• Invent the next mad team-tactics to shock enemies and make allies laugh.
  
• Combine cloaking, teleports, shields, jumpjets, EMP, napalm, gravity guns, black hole launchers, mind control and self-replication.
  
• Tiny flea swarm that clings to walls?
  
• Jumping "cans" with steam-spike?
  
• Buoys that hide under water to ambush ships?
  
• Mechs that spew fire and enjoy being tossed from air transports?
  
• Carrier with cute helicopters?
  
• Jumping Jugglenaut with dual wielding gravity guns?
  
• Meet them in Zero-K!

• OS: Ubuntu 13.04 or equivalent
• Processor: 2.0 GHz dual core CPU with SSE (Intel Core 2 Duo or equivalent)Memory: 4 GB RAM
• Memory: 4 GB RAM
• Graphics: 512 MB graphics card with OpenGL 3 support (GeForce 8800 or equivalent)
• Storage: 6 GB available spaceAdditional Notes: 64bit only. Big Picture mode is not supported

• OS: Ubuntu 17.10 or equivalent
• Processor: 3.0 GHz quad core CPU (Intel Core i5 or equivalent)Memory: 8 GB RAM
• Memory: 8 GB RAM
• Graphics: 2048 MB graphics card with OpenGL 3 support (high GT 500 series or equivalent)Network: Broadband Internet connection
• Storage: 8 GB available spaceAdditional Notes: 64bit only. Big Picture mode is not supported