Mark Incitti was recently requested by Bizarre Creations (developer of Geometry Wars) to remove the Grid Wars download link. Here is the quote from Mark's web site:
"We're beginning to feel the effects of the Geometry Wars clones on our sales via Microsoft now and are beginning a process to begin to more robustly protect our copyright and intellectual property."
"Therefore, I'd like to ask you in an amicable fashion to stop infringing our IP and pull the game 'Grid Wars' from the internet for download."
"I hope you understand and are able to do this without us having to take further steps."
So, where to get your GridWars fix? Here are fifteen recommendations.
(Scroll down for all the reviews)
1. Grid Wars
2. XWars
3. Echoes
4. Rainbow Wars
5. Veck
6. Bullet Candy (demo)
7. Neon Wars (demo)
8. RetroBlast
9. HGEWars
10. Grid Assault
11. Mu-cade
12. Base 2
13. Mono
14. Mutant Storm (demo)
15. Vector Infector
Reviews

Grid Wars
Probably the most popular Geometry Wars clone, partly due to the fact that it's free and playable on at least two platforms. The dual analog controls work well, but players without a joypad can play using a combination of mouse and keyboard. No levels, but the difficulty increases slowly with the addition of new types of enemies. A black hole appears from time to time, which you can use to your advantage since it sucks everything into it. Blow it up, and the amount of points you earned depends on how many objects were drawn into the dark matter. This particular technique called black hole harvesting is a heated discussion among many fans of Mark Incitti's shooter.
Most power-ups upgrade your shots or gives you a temporary shield, while bombs can be used to clear the entire screen. The game has gone through many revisions and what we have is the final version, plus it's unlikely to be updated since the author has moved on to other projects.
Name: Grid Wars
Developer: Mark Incitti
Type: Freeware
Platform: PC, Mac
Size: 3.3MB
Online High Score: No
Geometry Wars-like scale: 8/10
Rating: 9
Direct download link: http://worldofstuart.excellentcontent.com/grid/GridWars54.zip
Download page: http://worldofstuart.excellentcontent.com/grid/wars.htm
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XWars
XWars is a decent attempt to fill the hole left vacant by the forced withdrawal of Grid Wars. There are no configurable options yet, though gameplay is practically the same bar some minor sprite changes. Dual analog controllers are also supported in the latest version.
Your ship can be moved around using the W, A, S and D keys. The mouse can be used to aim at other vector shapes. Indicators shown at the top of the screen provides information on the next upgrade or multiplier increase at a glance. A worthy substitute, especially with a little more work. Made using the HGE engine.
Name: XWars
Developer: Ehud
Type: Freeware
Platform: PC
Size: 0.6MB
Online High Score: No
Geometry Wars-like scale: 8/10
Rating: 7
Download page:
http://www.gamedev.net/community/forums/topic.asp?topic_id=417391
Mirror: http://files.filefront.com/Xwarsrar/;6691038;;/fileinfo.html
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Echoes
Echoes is an arena shooter by Binary Zoo which consists of ten levels, with a different enemy type introduced on every new stage. Each have their unique strengths, weaknesses and require various strategies to deal with effectively.
The player loses energy when collision with an adversary could not be avoided. Remaining energy is shown as a counter on the top right of the screen, also indicated by the colored ring surrounding your ship. There are only three different power-ups to collect. One increases firepower, the other restores health while the third is a sort of bomb.
Zoots awards are handed out whenever a certain task is completed, with current achievements available to peruse via the trial accomplishment screen. To get a perfect score, all ten objectives must be attempted at the highest difficulty.
Name: Echoes
Developer: Binary Zoo
Type: Freeware
Platform: PC
Size: 10.8MB
Online High Score: No
Geometry Wars-like scale: 8/10
Rating: 9
Direct download link:
http://www.binaryzoo.com/games/echoes/echoes.zip
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Rainbow Wars
A side project from Volition designer Luke Schneider, part of the team responsible for the development of the Descent series. The background is practically empty, but destroying enemy ships will cause glowing particles to appear on screen. Bombs only appear as a power-up item, and is activated on the spot when collected. A power-up item will appear for every five thousand points earned which includes a black hole that only sucks in enemy ships.
Your ship is equipped with three layers of shield, and you lose one whenever an enemy ship touches yours. Destroying each wave of enemies will increase the level number by one, also replenishing your shields automatically. Losing all your shields ends the game, but you can continue from the last level attempted by selecting it at the main menu. Note that the easy difficulty will only allow access to the first ten waves.
Your ship also has the ability to warp and charge it's shot. Tap the left shoulder button on your gamepad to teleport, and hold the right shoulder button to prepare for a special attack. It's interesting to note that Rainbow Wars is an effort made with Game Maker in only thirty hours.
Name: Rainbow Wars
Developer: Luke Schneider
Type: Freeware
Platform: PC
Size: 2.2MB
Online High Score: No
Geometry Wars-like scale: 6/10
Rating: 8
Download page: http://www.volition-inc.com/Staff/LukeSchnieder
(click on design ideas to download)
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Veck
(Watch the gameplay video on YouTube!)
Veck was originally a competition entry for the Retro Remakes vector competition, which it won by garnering more than half of the votes submitted even though there were nine other entries. The level number increases for each minute that your ship remains intact, up to fifteen. Then the game loops back to the first wave but your score remains.
Weapon upgrade is automatic as well, bestowing the ability to shoot more bullets whenever the minute counter changes. No lives or shields, instead health is measured by energy which increments slowly but depletes if a collision with another object occurs.
Has the distinction of most bullets fired by your ship among all the games mentioned. The soundtrack is great as well, generating plenty of adrenaline rush as it reaches a crescendo. Full screen can only be enabled using a command line parameter, stated in a text file that comes with the zip package. For users with no gamepad, the mouse is not part of the control option although directional firing is still possible by mapping four other keys in addition to the standard movement.
Name: Veck
Developer: smayds
Type: Freeware
Platform: PC
Size: 1.6MB
Online High Score: No
Geometry Wars-like scale: 7/10
Rating: 9
Direct download link: http://dl.smayds.com/VeckSE.zip
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Bullet Candy
Bullet Candy is more like Robotron: 2084 than Geometry Wars, although the inclusion of dual analog controls make it a worthwhile inclusion into this list. You control a ship stuck in space much like the others, but enemies are able to shoot at you in many different ways. Lives can be earned either by collecting red power-ups or scoring 100,000 points.
Power-ups include lasers, triple shots and temporary invincibility. Bullet Candy includes a survival mode and an Asteroid Belt game, plus some secrets as well. Only fifty levels in the normal mode although most are designed to offer different challenges. For players without the luxury of a gamepad, the standard mouse and keyboard control combination can be used.
Name: Bullet Candy
Developer: Charlies Games
Type: Demo
Platform: PC, Mac
Size: 8.2MB
Online High Score: Yes
Geometry Wars-like scale: 3/10
Rating: 8
Download page: http://www.charliesgames.co.uk/
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Neon Wars
Developed by Reflected Games and BlitWise Productions, Neon Wars is another arena shooter that will only run properly if you have OpenGL 1.2 or above installed.
Your ship can only be moved around using the mouse, plus the primary weapon is fired automatically at the nearest enemy. Nevertheless, the one level included has no time restrictions and replayable at any time even though several power-ups have been disabled.
Name: Neon Wars
Developer: BlitWise Productions
Type: Demo
Platform: PC
Size: 2.9MB
Online High Score: No
Geometry Wars-like scale: 7/10
Rating: 8
Download page: http://www.blitwise.com/neonwars.html
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RetroBlast
RetroBlast uses vector shapes for objects and enemies, much like Geometry Wars but that's where the similarities end. Only mouse control is available, and players used to a dual analog gamepad will be disappointed with this effort. To shoot at an enemy, your ship must first be rotated to face it by using the left or right mouse button to turn. Bombs can be used to clear the screen.
The full version features a hundred levels but only the first eighteen can be accessed in the demo.
Name: RetroBlast
Developer: JGOware
Type: Demo
Platform: PC
Size: 2.8MB
Online High Score: Yes
Geometry Wars-like scale: 5/10
Rating: 5
Download page: http://jgoware.com/retroblast.htm
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HGEWars
HGEWars is a work in progress by Yuriy O'Donnell, and there is still plenty of development to be done although it's been around longer than any of the other Geometry Wars clones. The rating should not be taken seriously since scores are not based on the final version. Some fiddling with the ini file is required for the gamepad to work.
Weapon upgrade is automatic. The gameplay is quite faithful to the original but it may be months before the final version is released.
Name: HGEWars
Developer: Yuriy O'Donnell
Type: Freeware
Platform: PC
Size: 0.3MB
Online High Score: No
Geometry Wars-like scale: 7/10
Rating: 3
Download page: http://yurka.org/gamedev/
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Grid Assault
Grid Assault plays more like Geometry Wars than any of the other attempts stated in this article. The author informs that it's development was halted to avoid any implications that may arise from creating an exact copy of Bizzare Creations' Xbox 360 hit on another platform.
Enemies will only appear for the first six minutes. Dual analog controls are available in addition to the mouse and keyboard combination. Weapon upgrade is automatic for every ten thousand points earned, and you can use bombs to destroy all objects on screen. Most of the objects from the original can be found in this effort.
Name: Grid Assault
Developer: Wiebo
Type: Freeware
Platform: PC
Size: 5.3MB
Online High Score: No
Geometry Wars-like scale: 9/10
Rating: 7
Download page: Blitz for the masses
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Mu-cade
Using vector shapes for shmups is practically a Kenta Cho hallmark, but the celebrated Japanese developer had been toying around with dual analog controls since Gunroar. A combination of both Robotron: 2084 and Snake, your objective is to stay on the rectangular platform and knock other enemies off it by shooting at them repeatedly.
For each enemy pushed off the platform, the tail of your ship grows longer and the score multiplier increases. A longer tail does complicate matters a little as it gets harder to stay on the platform. If the tail of your ship is over the edge, the weight will drag the rest of the ship with it as well.
Fortunately players only need to worry about the front portion of the ship. The tail itself can be blown apart in exchange for a short burst of additional firepower. You will lose the multiplier in the process though.
It gets increasingly harder to stay on the platform as time passes, but an extra life is awarded for every 200,000 points earned.
Name: Mu-cade
Developer: Kenta Cho
Type: Freeware
Platform: PC
Size: 6.02MB
Online High Score: No
Geometry Wars-like scale: 2/10
Rating: 7
Download page: http://www.asahi-net.or.jp/~cs8k-cyu/windows/mcd_e.html
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Base 2
Base 2 is a game that plays more like Every Extend than anything else. The player controls a bit with the mouse, using the left button to activate the shield. Coming in contact with enemy ships when your shield is up will cause them to explode.
Some enemies are too large to eliminate in this manner, so your only option is to maneuver around them carefully. The green bar at the top of the screen indicates the amount of energy you currently have, and will depreciate whenever your bit touches an enemy ship with the shields down. Some energy is lost regardless of shield status when collision with large enemies could not be avoided.
Pressing the right mouse button activates the freeze bomb, which freezes all enemies on-screen momentarily. Extra lives can be earned by destroying enemies of the same color in a row, using a process called linking. Multipliers are awarded for long links.
The screen tilt can be rather helpful or distracting to players, depending on their preferences. A higher score would have been awarded if the toggle option was available from the main menu.
Name: Base 2
Developer: SimSimGames
Type: Freeware
Platform: PC
Size: 6.02MB
Online High Score: No
Geometry Wars-like scale: 2/10
Rating: 5
Download page: http://www.simsimgames.co.uk/
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Mono
Mono is a shooter from Binary Zoo that uses Robotron 2084-style controls, where the aim of the game is to change the color of the entire screen from black to white or white to black. Enemies will leave a splash of color on the playing field when destroyed, and the behavior of a hostile unit will change depending on the patch of color that they traverse on.
Power-ups can be collected replenish energy, shields, or radically alter your ship's firepower, although they only lasts ten seconds. Playing this game can be disorienting after a while because of the bright colors used.
Name: Mono
Developer: Binary Zoo
Type: Freeware
Platform: PC
Size: 5.5MB
Online High Score: No
Geometry Wars-like scale: 3/10
Rating: 5
Download page: http://www.binaryzoo.com/games/mono/
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Mutant Storm
Mutant Storm is an arena shooter developed by PomPom Games, in which you control a ship equipped with directional firing much like Geometry Wars. Instead of vector shapes, most of the objects in the game are represented in 3D.
It's quite unfortunate that your progress is only saved every ten levels, leaving most users replaying the same stages just to arrive at a save point.
Name: Mutant Storm
Developer: PomPom Games
Type: Demo
Platform: PC, Mac, Linux
Size: 4.3MB
Online High Score: Yes
Geometry Wars-like scale: 6/10
Rating: 7
Download page: http://www.pompomgames.com/mutantstorm.htm
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Vector Infector
Vector Infector is another release by Oddbob that resembles Geometry Wars, featuring fifty rooms filled with geometric shapes bent on your ship's destruction.
There are some notable differences when comparing this version with the console hit. For example, the only way to power up your weapon's attack strength is by collecting gems that vanquished enemies leave behind. The game also has a wrap around playing field, where sprites that go over the edge of the screen will appear on the other side.
Two control options are made available to the player. Pressing the Z key will cause your ship to fire in the direction it is currently facing. Shots can also be directed by using W, A, S and D keys. Looks very promising even if it's still in early development stages.
Name: Vector Infector
Developer: Oddbob
Type: Demo
Platform: PC
Size: 15.0MB
Online High Score: No
Geometry Wars-like scale: 7/10
Rating: 5
Direct download link: http://www.merseyremakes.co.uk/previews/testbuild8thJan.exe
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Some notables which uses dual analog or features vector shapes that did not make the list (for various reasons), but very playable nonetheless:
Circle Hunter by Swooshysoft [review]
Bubble Thing by Queasy Games [review]
All games copyrighted by their respective development studios.