Immortal Defense is a story-driven tower defense game in which you give up your body and life to become an immortal "path defender", and defend your home world from destruction, forever. The game takes place over millions of years. Is there anything you would give up everything to defend?
User reviews:
Very Positive (63 reviews) - 93% of the 63 user reviews for this game are positive.
Release Date: May 29, 2007

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February 11

v1.2.7 Patch Notes

- Endless levels now are not quite as endless. It's now much more difficult to last a half hour, an hour, or more, because the difficulty in those levels now scales faster the longer a level lasts. For instance, HP, spawning rate, speed, etc. all scale slightly faster over time. More enemies can appear onscreen at once in Raberata levels, and the Fear Points don't slow enemies as much in those levels. It should still be possible to last 10 minutes (to get the achievement for doing so), but now much harder / impossible to last an hour in one.
- Made the "Love 3" medal campaign level easier. Not by doing anything to the level itself, but by increasing the cache reward for the "Love 2" level. Now instead of 160,000 bonus cache as a reward, the player gets 260,000 bonus cache instead. It's still a good idea to save up as much money in Love 2 as you can, but it should now be easier to beat Love 3 even if you come into it somewhat cache-starved.
- Likewise made the "Love 1" medal campaign level slightly easier, by increasing the number of lives from 17 to 20, and slightly reducing the enemy spawn rate.
- Graveship starting HP nerfed a bit in the sixth campaign.
- Pride Points were a bit overpowered. I did some extensive testing where I'd play several levels that had all the Points available, spend equal amounts of money upgrading all the Points, and then play through the level, giving each Point an equal amount of money on upgrades, and the Pride Point almost always did the most damage. I didn't like that, but I didn't want to nerf it too much, so I kept its growth rate and its starting damage rates intact, but simply lowered its firing rate a bit. Now the Pride Point fires about 2/3 as fast as it used to, across all levels.
- Did some more testing, and Pride Points were still too powerful; reduced their damage growth after 30 kills (it's the same as the old formula prior to that, but less after that).
- Three of the levels in the sixth campaign, which were three 'boss rush' stages (85, 86, and 87, using the game's roman numeral numbering system, or 90, 91, 92 using the absolute path level numbering system which includes raberata levels) were made easier, changing the number of lives from 1 to 3, to give people some margin for error.
- Reduced the number of lives for the first two levels from 20 to 10. This is because, before, on the default difficulty level, even if you just stand there, you can beat those levels (with a low percent success) without shooting or attacking anything. So the number of lives was too high -- it should at least be possible to lose the first two levels, even though it's still very difficult to lose them.
- The 'Defender' enemy sometimes randomly spawned with a 0 defense rating (there is a random element to what its starting defense value is). I don't think that quite makes sense because it's supposed to be distinguished from the Form enemy by having a higher defense rating. So now I made sure that enemy at least has 3 defense when spawning, at the minimum. That might not sound like a lot, but when your cursor is doing 8 damage in levels 1 or 2, having at least 3 defense is significant. I also made its maximum defense now vary based on campaign, instead of always being 140 as a hard cap, it now ranges from 125 to 150 (5 more for its cap for each of the campaigns).

- Added help description mouseovers for the four bottom option toggles: shaking the gui, backgrounds on/off, path width, and stage select music choice, just to clarify what those options do.
- Improved the visual contrast on the manuals (enemies list, towers list, game manual, and similar). The background that the white text appears on is now not as bright of a blue.
- Likewise, improved the visual contrast for the leaderboard display, file loading (to play custom levels), file saving (in the level editor) (which all used the same code anyway).
- Lastly, improved the visual contrast for the help window pop-ups for the enemies, points, and lives/time/cache displays.
- Updated a few of the achievement descriptions on Steam to match the in-game descriptions (for those achievements which have changed since release).

- Fixed a bug that caused the formatting of the leaderboards to be jumbled. Leaderboards should now be more legible and appear correctly. Longer Steam names are shortened for the leaderboard for this purpose. They're shortened more in Japanese due to font width issues.
- Fixed a bug that made hellspace hard to unlock, particularly for legacy save files (now it doesn't count the percent success of the second Brother Bavakh battle).
- Fixed (hopefully) a bug that caused the success % ratio to not correctly go down when you first beat a level with a higher success %, then go back again and beat that level again at a higher challenge but with a lower success %, and if you didn't score a new record score. Previously it would raise your challenge score but not lower your success score in that unique case, but now it should correctly lower your success score.
- Fixed a bug that caused Noyaties 19 to have zero HP and be unable to be killed in the 'Cold Immortal' custom campaign (and presumably any custom user-made level as well).
- Fixed a bug that allowed you to complete a level on 100% challenge, with any% success, then complete it on a lower difficulty with 100% success, and get 100%/100%. Now instead, the success% is not updated when you complete a level on a lower difficulty than your previous highest difficulty, only the challenge score is improved. I'm ashamed it took me this long to figure out the logical problem in how I had coded it, but it should work correctly now.

Here's an illustration of how that last bug fix works now:

1) let's say your first attempt at a level is: 0 challenge, 30% success
2) you then try again at 50% challenge, and get 10% success. both of those are updated, it doesn't keep the old higher success rate of 30% anymore.
3) then perhaps you tried again at 0 challenge, got 100% success, but neither value was updated, because it's a lower challenge level than the highest challenge level you completed the level on. previously, the success would have incorrectly been updated to 100%.
4) and then perhaps you tried the level yet again at 50 challenge, and got 15% success, 5% higher than before. then it'd be correctly updated with your success going to 15% instead of 10%.

So now you can't get 100/100 merely by beating a level once at 100% challenge at any success rate, and then playing it again at a lower challenge and getting a 100% success rate, giving you 100/100. This is *not* retroactive, your old scores will remain. It's just the new scores that will from now on be updated using this system, where the success rate will not update unless you are completing a level at or above your highest challenge setting that a level was previously completed on.

2 comments Read more


“Immortal Defense is a tower defense game for people who abhor tower defense games. Or people who like them. Or people who think they're okay.”
Anthony Burch, Destructoid

“Immortal Defense takes a simple, oversaturated genre and elevates it to another level entirely. The existentialist storyline is not only compelling and thoughtful, but it's probably the best explanation for "turret defense" gameplay I've seen yet.”
9 – Derek Yu, Game Tunnel

“The brief text sequences between levels carries the story--to fight in "pathspace," you have foregone your body and normal existence, and the concerns of the people who are sworn to defend seem increasingly irrelevant to you, in this very different existence. I typically think this kind of backstory is irrelevant (and often poorly written), but here it's almost haunting--nicely done.”
10 – Greg Costikyan, Game Tunnel

About This Game

Immortal Defense has been widely praised for the game's storytelling and unique twist on the tower defense genre, many consider it a cult classic of the subgenre. Its story was written by novelist Jeanne Thornton, and its universe is based on the novel Raberata by Robert Bisno. This new Steam release features many improvements over the original release: Steam achievements which grant gameplay bonuses, leaderboards, improved graphics and performance, widescreen support, an improved level editor, and much more.

WARNING: This game involves a lot of flashing lights and visual effects. If you have sensory issues, such as epilepsy, this game might cause more problems for you than other games. There is a way to turn the visual options down, but even with all the options turned down, it can still be quite flashy.

Immortal Defense has a story-driven campaign with 100 core levels and 50 optional side-quest levels (which can be completed for bonuses that help you with the core levels). The game takes about 20 hours to complete everything in. The game comes with the soundtrack, which is by Long Dao and classical composer Walter Eres. There are also Steam Cards which were hand-painted in watercolor just for this Steam release.

There are 26 types of enemies, each with its own abilities and unique interactions with one another, and 11 types of towers, each of which goes through different forms as they are upgraded, and each of which gains new abilities as the player collects achievements. These are not standard enemy types like "flying" or standard tower types like "long range and slow"--you haven't seen these before in other tower defense games. The game also comes with a level editor, with Steam Workshop support, and is pre-packaged with an extra 62 levels created by fans.

Note: The game was first released on May 31, 2007, and was updated with new content in 2009, and then again significantly improved for its Steam release in August 2015.

System Requirements

    • OS: Windows XP, Vista, 7, 8, or 10
    • Memory: 1024 MB RAM
    • Graphics: 128MB
    • DirectX: Version 9.0
    • Storage: 350 MB available space
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Very Positive (63 reviews)
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