Comet Crash: TD meets Casual RTS

Nearly 4 years ago i wrote about the great flash based Desktop Tower Defense game.

Over one year i have been playing another great Tower Defense game, this time on PS3: Comet Crash.

But something else first: Nearly one year i had to see the prove for TTP (time to penis) here on Game Design Reviews. So now i think its time for a new review ;) (Of course i can never reach the workload kryst invests into his last page-spanning reviews, but i hope i can at least present a good and sometimes overlooked game here).

As you might have seen on someof my previous reviews, I’m a big strategy / tactics fan.

This is a nice introductory gameplay video (not done by me).

So in this review i will try to give an overview over the things i liked about the reatltime strategy (RTS) and tower defense (TD) genre mash-up: Comet Crash. I will also try to list what i think makes them good from an objective Game Design Review point of view. (Warning: i will write quite subjective while trying to stay objective!)

Target audience? Me! aka the casual strategy lover

Of course i have to admit my love for X-Com (liking the second under water part even more than the first) and did lose some weeks if not even months of life time to Civilization 1, 3 and 4 (but I am quite disappointed so far about Civ 5).

But probably I wouldn’t consider myself totally hardcore for that genre, because most hex based military stuff with huge world-maps always turned and still turns me down. Instead i had my share of Famicom / Advanced Wars and typically try out a lot of casually appearing strategy games on PC, mobiles and consoles.

So i also tried some PS3 / PSN games where Mushroom Wars was quite nice, but basically only a Galcon clone which tries to spiff-up the condensed Galcon gameplay with a bit unclear/undefined/to casual additions. But still a nice try by Russian Creat team. (And i guess it is selling quite well with that casual appeal?!)

In the last few years i played many more flash based Tower Defense games. But i was especially search for TD games on PS3. So i tried many and was quite often not that satisfied: Crystal Defenders – became quite boring after a few hours. Savage Moon – just used 3D to much. And Pixel Junk Monsters – which was just to unclear in its goals for my taste. But probably i was just to spoiled by the great Pixel Junk Racers, with its totally goal driven game design (and damn hard difficulty curve).

Last but not least Comet Crash was released end 2009 … and boy did we play it a lot (David, Sascha, Björn, Me). I truly felt like seventeen again ;) We also tried out some Multiplayer (which i will only cover barely at the end of this review), but mainly played a lot of Singleplayer Sessions, including the Add-On (which I’m trying to complete in the last few weeks.)

This is TD

Comet Crash starts perfectly by not presenting any story. At least there are no cut scenes, no dialogues, no intermissions. Just pure gameplay suited to the casual audience for Strategy games.

classic 2D-squared-grid-fields strategy. I just love spatial gameplay :)

The game has clearly distinguishable grid based tower defense gameplay, where everything is perfectly visible on one screen (wonderful FULL HD). While the camera is never moving, it is 3D with fully pixel lighting, shadowing, bloom’filtering and normal mapping – all in an classic isometric, instead of a perspective projection.

Gameplay wise it kept the classic TD concept: Enemy units attack in waves, but merely all the time; while the player builds towers to defend.

And yet it is more than TD

The game design is a simple but great extension on TD, to easily bridge the gap between TD and RTS genre:
Extended by allowing the player to also build units which auto-attack the enemy, who has a base defended by turrets as well. So its more like TD vs. TD – and multiplayer is actually exactly that. Construction buildings build units, but cleverly they “stored” (and displayed as a number) until you unleash an attack wave – very TD alike.

Further more extended by gathering resources, simplified to fit casual/console gameplay, yet it creates much tension by the simple fact that the resources are animated / fly past the screen. This simply creates tension because one can lose them, i.e. before you can harvest them, they already left the screen. Wasted!

Towers vs. towers, building units, collecting resources.

And also extended by a controllable player ship, actually more like the incarnation of a PC mouse cursor, just slower with heavy armor and more implications. David mentioned to me that its perfectly taking the weak-points of a console and turning them to gameplay strengths. (reminding me of the mental Dune2 predecessor Herzog):
 – gathering resources with the joypad is not annoying, its truly a nice challenge
 – you can in-directly fight opponents in multiplayer by stealing their resources (you have a tractor-beam to carry the rocks and players can rope-war on them), making them distracted/nervous when hovering over their currently watched playfield
 – and you even lure them into your air-defenses, which can attack player ships, which makes above mentioned “try not to waste resources” even harder as you have to avoid the enemy base defenses.
Don’t try this at home – with your average PC mouse-cursor or schmartphone touchscreen!

Simple and clear mission design

Basically all above mentioned points result in nice “puzzle” gameplay, where you have to
1.) learn how to defend in a given level (proper level-up / build flow) and then
2.) learn how to attack the enemies base properly (against its build patterns.
This is quite simple yet perfect. Its not a gigantic world to explore, not 85 character ranks to level up and not 25 races to try out. Its just 48 levels of “normal” brainteasing strategy gameplay.

What i call “puzzle” gameplay. Once you understand what to do, its quite easy to accomplish.

Its also greatly using the “classic” attack/counter attack pattern, where you have to learn which elements (enemies, turrets) can be countered by which other elements. The whole game seems quite simple when written on a papersheet
still it works flawlessly as you are teased to use your brain against the AI that seems at times more scripted than coded. But it still manages to stay casual when forcing you to play a few levels in a few hours. It does not reach the hardcore side of strategy/tactic games, where less than a full weekend will not even allow you to progress through “easier” levels.

It just sticks to a few great concepts. For example, the game has only one flying unit (”drone”). Because it seems that nothing more is needed to extend TD into a nice casual RTS: In some levels you will not be able to use drones due to good enemy AI defense. While in others drones will be the primary dominating strategy. Well, at least once you tactically understand how to build up your defenses strong enough to actually find the time to build this expensive unit.
I wrote “understand” but its actually more “learned the hard way” by losing and replaying. Which typically annoys me a lot in other games. But in Comet Crash it is really fine as most “battles” last less than 30 minutes and i can get through a level with 3 iterations! Perfect for playing my 2 hours from ten to twelve when I’m in need of a little success to finish the day nicely.

Air attack: drones for the win!

Because the concepts appear a bit simple when later on analyzing them, one could think the developers where not able to come up with a more complex game (its actually only 1 programmer/designer guy and 1 level-design girl :) . For example the AI never fights with you for resources but just has an unlimited amount of it.
But obviously when you develop something for more than 8 weeks you have A LOT of time to over complicate your gamedesign instead of releasing polished gameplay. Thus kudos to Pelfast for keeping everything perfectly simple. May the sales be with you! :-)

Small additional ideas and extended basics

Its good that in the mood of TD gameplay, your towers are not attacked by the approaching units (different to RTS where this is one of the first things that happens). So its less an RTS but more a rather relaxing SimBuilding game – just one with battles ;) .
I once heard whats needed to learn good design: Understand the basics, then twist them. So later you will be able to build towers next to the enemies towers, and those towers will attack each other. So you will battle with the enemy about who has more resources and upgrades them faster.

Again some mixing occurs, this time with the games add-on. It nicely throws the relaxing Sim atmosphere overboard by later adding some uber-missiles which will actually destroy anything (including your base / turrets). But this is used in the level design to only repetitively destroy manual spots, which you can clearly identify after a few shots. Instead of overcomplicated AI based or random attack patters on all towers on the map. Once again its a more or less casual TD and no hardcore strategy game, and it works so well.

Wo die explodieren wächst kein Gras mehr!

The GUI is not pretty, but clearly tuned for easy use and understandability: Health + money + units build (and ready to be released). Its also good to see in later levels how much the enemy has build, so you know when the limit is reached you need to have good defenses for the next attacking wave.

Comet Crash has a very good idea for a direct building menu: its always where you need it (whenever you open it, it sticks directly next to the the player ship). This is nice in singleplayer and allows for quite faster game pacing, but in multiplayer it helps a lot and is from utmost importance for quick action based gameplay.

The add-on opens one little flaw, because the menu is in the original game intended for 2 rows of icons, and in the add-on further “scrollable” rows become available. Sadly one can miss this, as there is no indication on the new scrollable extended area.

Another idea helping the resource gathering (turrets shoot resources, so they “explode” and present yellow money-numbers to be gatherable) is the nice range concept: Collect + signs to extend the ships range, in which money is automatically sucked in. Without a large rage, you have to manually collect the money. So in early gameplay you collect a lot, and after extending the range you can in late gameplay forget about resources and just concentrate to execute your strategy properly.

Later in add-on exchanged this range concept and “turrets shoot resources down”, against resource buildings (nice twist here) and instead of range the + symbols allow for a nice shields/health-bar upgrading. I think this is an important point many add-ons / sequels miss: To change some game basics with the add-on to make it more a variation, not simply a level-pack.

Last but not least the game features a nice upgrade system for the turrets. It works well as is not overdone, just the typical TD choice: build more to get more “route” for the enemy to walk, or upgrade to have more power on limited space. Balanced as with every other TD: upgrades are better than new turrets. One flaw is just that the visuals which show the reached upgrade level for a player owned or enemy turret are quite hidden, as its only some black stripes on the turret base.


I only have a few words about the multiplayer mode, because I am not the right one to judge it. Why? I must admit that’s simply due to the fact that i was always overworked / stressed when playing it in multiplayer, and thus the game lost its casual appeal. It made my head spin because you have to decide so many steps so fast, which was just to much for me.

Multiplayer: its never as easy as it appears on this screenshot.

David mostly criticized the 3 player mode, because it simply doesn’t work well due to the fact that a 2d map has 4 edges. Of course that’s given, but some minor gameplay tweaks might have helped here. Instead the 3 player maps which try to be a bit more triangular in their design, like cutting 3 pizza-pieces from a rectangular party-pizza, still problems remain. Like for example the fact that when two are fighting about resources or attacking each other, the third always gains an advantage.

Audio & visually simple, yet suited

The game features quite nice low-poly 3d graphics, which really show how much quantity the PS3 can push. In the sequel, the great dragons roaming the screen are made by thousand lowpoly tank objects attached to form the giant snake body.

You just have to love those dragons in action.

So not only instancing (or i guess geometry shaders) but also pixel shaders are used very well for a rts / many-units game. Also i think that the bloom filter (glow) is not over used but still helps to improve visuals a lot.
Lowpoly meshes are in a distinct the slightly techno-like style, personally my favourite style without textured units – just flat shaded. And i can easily understand that others see the game as quite bland, while i think it looks perfect for a futuristic RTS.

Comet Crash features a nice soundtrack, but a few more songs could’ve been better. But I might have missed some tracks, as after a while I disabled all music anyway, so I could concentrate on the more difficult levels. Also good – read simple – audio effects, with good ideas like a “heart-beat like drum” telling you when the enemy has nearly reached its production climax/limit and will attack. Also it uses PS3s ability to play 3d sound around the player. So you can hear important events far away, while still only the action next to the player is “loud” and builds good tension. So that no extra unnecessary annoyance is experienced by hearing the full battlefields action sfx. (Since more than 8 years we can hear SO MANY sfx in parallel on hardware and even software mixing, but in my opinion it never helped any game to have more than a good set of rather few sfx and ambient tracks/music hearable at once. So i expect many good games like StarCraft to have spend many coding hours to choose when and what sounds to play/feature and which to reduce/silence).

All in all

I would rate Comet Crash a 10/10 based on its clear intentions and success in fulfilling them. I would have loved to work on it, to be able to create such a creative yet still simple gameplay – as my ideas tend to be overcomplicated all the time.

And whenever in the future I might try to do something RTS/TD alike, I bet I will try to imitate Comet Crash for its sleek and fluid feeling and perfect balance of easy tried and tested ideas combined with nice additional twists. For me it definitely is one of the best – if not the best – indie / 2 people developed games of this century. And at least the 2009 gained awards for best game seems to show that others thought alike :)

Daniel Renkel

Daniel 'sirleto' Renkel is a true indie game developer (at heart ;) and a part time simulation engineer (space- & aircrafts). He's studied computer science at the university of Darmstadt, Germany and has a background of 8 years as game developer (assistant projectmanager, game designer, associate producer and technical artist). He worked on a whole number of PC and console games including the Aquanox series. Visit for more information about this current android mobile phone games.

3 responses to “Comet Crash: TD meets Casual RTS”

  1. gerald berg


    I just read your excellent article on Comet Crash; one of the best I have ever used.

    I would like to hire / work with established PS3 developers on a new project for one of my companies. Might you offer a path I can follow to meet PS3 developers?


  2. sirleto

    no, sorry. i do not have any personal contact to ps3 developers nor specific ideas how to find/approach suitable companies.

    you probably have to go the hard way, looking for smaller / casual games producing companies (on ps3) and check their websites for non-self-funded development. those companies will clearly like to work for / your customers as long as you offer enough money.

    kryst and yc would probably mention here

  3. Catherine Meyers

    Hello Game Design Reviews,

    My name is Catherine Meyers, I’m the admin of a high traffic web/blog directory (PR5) and a games web. I’ve been reading your blog and it’s articles, and would like to offer you a link exchange with my sites, hoping that they can serve as valuable entertainment to your site’s visitors and more importantly help improving the web traffic of Game Design Reviews. If you are interested please let me know.




Game Design Reviews is a Blog used by a group of game designers from Germany to publish and discuss their thoughts on various games. The blog consists entirely of reviews of games. Each review focuses on the important game design ideas and concepts of that particular game. We also run a second, more informal Blog called Game Design Scrapbook.


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