Circuit Defenders is a fun little game and can be quite the challenge up to a point. In the "classic" game, there is what I'd describe a "hump" in playability. During the start, you have to be strategic about tower choice and placement as you are earning limited money for destroying the enemies. Since the value of each enemy destroyed goes up with every level, eventually you can earn so much money that for all practical purposes it becomes unlimited. At higher levels you end up earning money faster than you can build and upgrade towers. This leads to the game actually becoming easier the longer it goes on. If you make it past level 100, you can essentially play forever.

The game can really be taxing on computers even with fast processors and graphics cards. At higher levels when there's a lot going on, the frame rate drops dramatically. My 3.06GHz iMac (ATI Radeon HD 4850) struggles to stay above 15 FPS, and on my 2010 MacBook Pro 2.4GHz (NVIDIA GeForce 320M) it's not unusual to have it drop to less than 5 FPS.

Great little game!

Downside is, i discover a new quirk, UI oddity, usability snag, or other problem with it almost every time i play, report them to the developers, and get... SILENCE. Well, more a kind of acknowledgement, followed by nothing being done. Once appeared to have a bright future, but development seems to be concentrated on their new releases, with Circuit Deffenders being mostly ignored except for basic maintenance. It feels somewhat incomplete, like it needs many more versions to become smoothed out.

The short list:

- No problem loading chosen circuits upon loading the game, but all the user gallery previews are missing in action of late (show: N/A). Have to bring up the web site to view the gallery, then try to find the levels in the game itself, as all levels are required to be stored on Sector3 servers.

- A handful of minor rendering bugs

- The level/circuit editor is seriously clunky, having developed it's own list of peculiar inconsistencies. One moment it will allow placement of a component in a particular position, while the next it won't; lets you put a component within a certain proximity of another, then won't in another location; display of a level in-game can vary widely from it's design or preview; often components cannot be placed where plenty of space is available, yet i've encoutered finished user levels which defy placement rules.

- Circuit preview quality is... bad.

- The game is poorly balanced. It depends on the circuit played, of course, but the typical experience has a level starting quite challenging, perhaps increasingly or decreasingly as levels pass, then becoming suddenly dramatically easy or difficult.

- If you ARE able to get over the "hump" in the game, your score progresses as slowly as ever while money (which is what you mostly get for destroying enemies) runs amok and you can buy and build as fast as you can, until the screen is jammed or (see next point), which means getting a score high enough to top the lists or just reach maximum rank is a matter of going away and letting it play itself if you don't have a high tedium tollerance.

- The game engine (Unity i believe) gets entirely overwhelmed too soon in play and frame rates become dismal even on a fast machine having a good video card, with the game making little adjustment to help correct for this, other than slowing game speed (and thus response also).

- Too few keyboard shortcuts, and most aren't configurable. An emergency arises and you get your butt kicked while trying to click the mouse through the clunky interface to get what's needed.

- I don't understand the mysterious "Shield Towers" powerup, of which there is only 1 to begin, and no others ever appear.

- In some ways the UI is shy on information that would be useful, while in others it's heavy on the unnecessary.

- No score advantage to releasing enemy waves early other than being able to knock them off quicker if you've already got ample firepower. i.e. Early it the game it gets you killed. Later it's inconsequential.

- Some weapons are dramatically innefective for most of the game in most circuits as they do little against the enemy units most common in later stages of the game, when fewer unit types are common.

I could go on at length, but it all gives a deceptively negative impression, as the game is enjoyable with the right circuit and difficulty level/game variant.

Unfortunately, there aren't many circuits which aren't user-created, and so many user-created ones have no unique concept; mostly what i call "scribbles".

Ah, that brings to mind a final couple points i nearly forgot:

The high score browsing UI is decidedly odd and inadequate for the number of game variations, lumping scores together in broad categores. It also lacks highlighting for one's most recently played game.

The UI for browsing the User Level Gallery is likewise inadequate; displaying only 8 of more than 500 currently available levels at a time, with no way to jump forward or back quickly, or specify a particular level.

Therefore, regardless of what sorting mode is employed viewing a significant number of options takes ages, especially as each set of previews must be downloaded from the server. Few levels have actually been used or rated much, likely for these very reasons.

(or perhaps a clue to why the game is neglected by devs?) With teensy poor-quality thumbnails, there's little basis for deciding which circuit is worth trying.

NOTE: Larger previews ARE available when viewing the gallery on the web site.

Wow that game is fantastic, i played to level 153 and then i lose :D
Great game!

What is your mac spec? Model and graphics? We test all of our games on our G4 emac up to an 8core Mac Pro, with plenty in between, so a lockup would indicate something specific to your machine. If you let me know your specs, we will do some testing here. We cant fix it in a next release if we don't know what the problem is. Cheers :-)

Download doesn't seem to offer a usable demo. Asks for a serial number to be entered before playing.

Wow, This is the first program in years to completely crash my Mac.
Complete freeze with skipping sound like a stuck CD.
Wait for the next fix.