Tower Defence Games : temporal or spatial problem ?

You guys ! Need your help !

I have read an excellent article published on 2012 by Pr Wetzel : « Effects of Representation on Solving Complex Spatial-Temporal Problems ». Pr Wetzel analyze that a TD game is a time representation. Or people often treat temporal problem as if they were spatial problems. Or, « Since the unit damage is constant, the goal should be to find places that maximize the active time. »

Of course, Tower defense games are plenty of spatial problems. You have to buy towers and build it so as to extend the cover of the wave’s way. But I’m only talking of the reasons you lost against a wave in a challenging level ou a challenging game. Why I have lost ? I’ve tried several strategies and I don’t understand why. The point is to know if I lose because I apply some spatial’s problems strategy whereas it’s a temporal problem ?

Please let me give you a first example with this level of Radiant Defense, excellent Android game I’m currently testing. What’s the matter ? On this level, there are 12 waves. At the beginning, it’s quite easy. I can maze the way, building some modules so I try to build as much as I can. But unfortunately, I’m not rich enough to buy and upgrade lots of tower. Problem, the 11th wave is a range of very numeros strong ennemies.

I can shoot some of them but there are too numerous. If I try to increase the number of tower, I can’t upgrade all of them and I need strong towers to destroy them. Can I sell my towers and build new one ? No there’s a lack of money.

These one are spatial problems’s strategies. Whan I try to extend the cover zone, I lose. Why is this a temporal problem ? Easy ! If I buy three towers and upgrade them to the maximum, there are able to destroy a part from the wave. The problem is there are too numerous ennemies. Some towers waste their time destroying one ennemy whereas a new one comes behind.

So the problem is how I can increase and maximize the activity period of these three towers ? Slow the ennemy ? I have found the solution. Waves are trying to find the shortest way to reach the exit. So if I build a vertical wall, waves come near this and then try to pass. Ok ! If they come in the direction on the wall, they lose some time. They are slow down. And if they continue to progress near the wall, this can extens the duration of the shooting activity of my tower. So I build three towers at the top of the wall and with this strategy, I am able to destroy a big number.

It doesn’t solve entirely the problem. I need to buy and built another towers to be able to destroy the entire wave. But the fact is this helps me to destroy the majority ! Yeah ! It’s been a temporal problem.

 

May I give you another example ? This is one level from Zdefense, a challenging mobile game inspired from Hex Defense. Very good game !

At this level, waves come from the left. They can pass throulg all cases and reach the exit. The first strategy I’ve tried consist in build violet wall to create the biggest way I can to slow down ennemy. Then I tried to build and upgrade towers to extend the cover zone. And I lost ! I lost because one of the last wave consist in a very big number of ennemy I am not able to fight against.

Of course, I’ve tried to create a bigger way, build more towers but I lost. My problem is that I am not able to build a infinite number of towers and upgrade them to the maximum. So the problem is not how to build new towers but how oblige waves to come several times in the cover area of my towers ? A first part of the succesful stragey consist in create way to oblige waves to do that. The second part consist in modify the way during the party so as to oblige way to follow the way, then return and then come back. So to follow the way in a direction, then in the other direction.

It was very difficult for me to find and apply this solution !

 

This is a last example, extracted from a level of Giants and Dwarves TD. This is a challenging excellent game inspired from Kingdom Rush.

These are two waves. During a wave, a giant is going into the exit. He is very strong, he walks slowly. I can build and upgrade my towers to shoot against him and I now I am able to destroy it before it reached the exit. But this giant is very strong and I can’t destroy it before the next waves come. Next wave consists in a group walking very quickly. Problem : the towers shoot in priority the giant and not the short wave.

So it is able to walk and reach the exit without any lost. Is it a spatial problem ? No, the fact I build more towers won’t help me because I now the existing ones are able to shoot. The problem is that the wave is very quickly and the towers won’t attack them in priority.

So the problem is to find a way to increase the activity period of my towers against this quickly wave. And I’ve found the solution : build some soldiers caserns. When the meet soldiers, wve stop and is forced to fight. Of course they will win because soldiers aren’t strong enough. But my towers decide to shoot them and not the giant. So I am able to destroy the quickly wave in the first part, then attack and win against the giant.

 

So the fact is when I lose several times against a wave in a Tower Defense game, the problem is I try to apply some strategies that are spatial strategies. Whereas the problem is in reality a temporal problem. So Pr Bretzel could be right : we treat temporal problems as if they were spatial problem. And because it’s difficult for us to devine it’s a temporal problem, to find pertinent strategies according to this goal, we lose.

My question is : what do you think about that ? Have you got some examples of challenging games/levels in which you have lost several times ? What kind of problems have you tried to solve and why have you defeated ? Is the distinction spatial/temporal problem pertinent according to you ? Do you know some scientifical publications about this themactics ?

Thank you a lot for your answers !

 

 

Hands of War TD

Sorti en 2008, Hands of War TD est un très bon jeu classique. Vous devez défendre votre nation contre une invasion armée et unir les 7 factions dispersées d’un clan. Obscurcie par la présence des forces du Mal, la carte de l’Empire apparaîtra au fur et à mesure de vos batailles victorieuses.

Design Jeu Tower Defense game

MAJ : 07/04/2015 : Plusieurs développeurs ont réagi positivement au concept du jeu ! Le jeu pourrait être développé pour internet fixe mais il a également un design optimal pour le mobile.

U2D : 07/04/2015 : Manu game devs like my td concept and consider it may be a very good mobile game.

 

Pendant mes vacances, j’ai eu l’occasion de me pencher sur les jeux de tower defense. L’inspiration m’ayant pris, j’ai composé un jeu. Ce jeu est basé sur le principe de boules tombant du plafond et roulant sur des plateformes inclinées en direction d’une sortie. Pas totalement innovant puisqu’il existe un jeu du genre. Mais j’ai voulu développer le concept en proposant quelques niveaux originaux.

During my Hollidays, I’ve designed a Tower Defense game. Guess it ! It’s based on balls falling on inclinate plateform until they reached floor. No, it’s not the first game using this concept but I just wanted to develop this one and design original levels !

 

         Oui mes dessins sont proprement affreux. Le premier niveau est un basique pour s’habituer au concept. Les balles tombent du ciel et viennent remplir un cercle au bas de l’écran. Lorsqu’elles tombent dans ce cercle, le joueur perd un point et la vitesse du jeu s’accélère.

Yes my drawing is quite awful but you’re an imaginative guy, aren’t you ? This is the first basical level. Balls just falls and follow the path until they reach a circle. When they reach it, player lose ont live point and game speed increase !

               2è niveau. Aïe, certaines parties en pointillé sont plutôt fragiles ! Des boules peuvent transpercer le sol et passer à la plateforme du dessous. Cela complique la stratégie à mettre en place !

This is the second level. Just realize dotted line are breakable. A ball may destroy it and fall below !

 3è niveau ! Mais, ce ne sont plus des plateformes ? Il s’agit de rampes sur lesquelles les balles glissent, sont projetées dans les airs jusqu’à atteindre le cercle final.

This is the third level. And now balls slide from one rail to another.

 le 4è niveau n’est pas mieux. A certains moments du jeu, la carte se divise en 2 et il faut gérer deux sous-cartes en même temps ! Comme si ça ne suffisait pas, un canon peut propulser les balles sur les points X et Y.

This is the fourth level. Ouch, map can sometimes be cut in two ! This mean you will have to play simultaneously on two maps ! Too easy ? Not too ! Some bals will be shooted from a canon on points X or Y.

 Le dernier niveau designé  ! Les croix sont mobiles et convergent tantôt vers la gauche et tantôt vers la droite.

This is my last level ! With mobile rail !

 

Reposant sur des cartes originales, ce jeu nécessitera une bonne dose de stratégie et sera plutôt difficile. Je cherche à présent un développeur qui serait intéressé pour reprendre et développer le jeu ! A disposition pour travailler ensemble ! J’ai imaginé le déroulement de chaque niveau, le nombre de vagues (plutôt peu élevé), les options et j’ai même quelques idées de cartes supplémentaires s’il en faut ! Postez un commentaire si ça vous intéresse.

Based on original maps, this game is a challenging tower defense ! Now I’m looking for a developper which want to take and develop my concept. Happy to work with you ! I’ve of course designed level, waves incoming and if necessary, I can design new maps ! Please post a comment if interested !

 

 

TD Games, blocks and cash machines !

In Classical Tower Defense games, you evolve on maps where waves just follow a linear way in order to reach the exit.

This is a screenshot of Gemcraft TD. Waves only follow one way.All you have to do is to buy and build towers in order to fight waves.

Lots of players prefer to play with these games and I understand that. When you play TD games, you just want to buy and build towers in order to fight waves. It’s naturel, isn’t it ? But let me ask you one question : what is the goal of Tower defense games ? To fight and win against waves, of course. But how ?

You will shoot as much as you can against waves. But if it is possible, you will try to slow down their progression.

There are several ways in which you can slow down waves. Let’s have a look on this map of the excellent game Kingdom Rush. Some towers may do it. You also can build a casern and ask to your soldiers to walk up on the waves’s ways ! Soldiers will fight against waves, slow down them, maybe kill them ?

Amazing ! In lots of TD games, towers have several functions. They of course can shoot against waves or slow down them. Let me introduce to you a sub-genre : mazing tower defense game ! In these games, your map is empty ! Ouch ! Waves will choose the shortest way to pass through the map and go to exit. In this kind of game, towers will have two functions. First of all, shooting against waves and killing them. Second function : building a way, the longest way you’re able to build.

This is a map of the game Revenge of the Stick. Sticks get out of the computer and try to leave the desk. Your strategy ? Building as many towers as you can. Upgrade them. Build a long way from the departure to the arrival.

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And what happens when you havn’t enough money to buy and build enough towers ? It’s a mazing TD but you aren’t able to build a way which is long enough. Or waves can go through another way… and you havn’t enough money to buy a tower and close it. What about horizontal tower defense if waves are stronger than your fighting force ?

Easy ! I would like to talk about tower defense games in which you can build… blocks and cash machines. You can’t shoot waves with that but these are very useful. There, you need to define a strategy allowing you to build either towers, blocks  ! The fact is you can’t win if you don’t buy them. For the moment, I’ve seen three kind of blocks.

– You can build blocks in order to build or to modify a way.

Blocks are cheaper than towers. For example, look at this screenshot of Traps and Sorcery. Two ways can be used to go to exit. You can’t defend these two ways at the beginning of the level. You must forbid the access of one way to waves… What does matter is the following : If you buy a tower to close a way, maybe waves won’t come near this tower. So this tower will be used only as a bloc. Isn’t that expansive ?

In the game Traps and Sorcery, you can buy some rocks and build a way with it. Rocks are very very cheap. It’s interesting to buy them and build a way if you can do that. This allow you to build more towers.

The first screenshot is extracted from the challenging game ZDefense HD lite.This game is a mazing tower defense. Some maps are totally empty, you must build a way from A to Z.In others maps, walls have already been built. Waves can reach exit by different ways. You must close some of them in order to build a long way.The point is you can do it only with towers.The second screenshot is extracted from difficult mobile game Mini Droid Defense II Lite.In this game, you can buy towers but also blocks. You sometimes must slow down waves and it’s less expansive to buy blocks than towers.Of course, if you can buy blocks, you are able to continue building a way AND upgrading existing towers !

In lots of Tower defense games, building blocks is just a possibility. You can win only with towers, without any bloc. That’s why I think it’s better to be forced to buy several blocks. It’s the case with a game like Traps and Sorcery I’ve already talked about.

Gaia Defense is such an interesting TD game ! Quite challenging ! And a very original horizontal TD game ! In this game, you don’t have to kill all waves, just the most part. It’s possible to buy some blocks because you want to slow down progression of waves. You know waves are able to hurt blocks and destroy them.

The question is : is it useful ? Gaia Defense is a good example of a challenging game in which you seem to have several strategy and must define the best one !

In Horizontal TD games, you often can buy and build some blocks. Of course you know the so known Plants vs Zombies must play !

In this kind of game it’s possible to buy some blocks, building it on waves’s way in order to slow them down. Lots of horizontal horizontal TD games are based on this mechanic. You know you will lose money because blocks will be destroyed. But it’s important. Because towers need more time to kill them… Or because you need time to build more towers…

Blocks are very useful to slow down ways or build mazes, yes. They have another functions ! In some towers defense, blocks are necessary… to build new towers. Funny, isn’t  it ? And excellent idea if you want to force players to buy and build blocks before building towers !

Yes horizontal TD games are original games !In Paper Defense, waves can go from the left, from the right but also… from the air !You can build some towers only on a wall.But unfortunately, you can’t build enough towers to destroy waves.And you’re not able to reach flying waves.	Your solution ? Building horizontal and vertical walls. The more walls you build the more towers you are able to build !Of course, if you build vertical walls, you will be able to reach and shoot against flying waves !
	This screenshot is extracted from Sanctum, a mazing tower defense game.At the beginning of the level, map is empty.First or all, you must build a way with blocks. Then you have to decide if you want to build towers on wall or not.Interesting !

Great ! we have seen some examples of tower defense games in which you may buy and build blocks. What about buying machines producing money ?

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– Ah money ! Money ! In many tower defense, you havn’t enough money to deploy an efficient strategy. So it’s necessary to win money. How ? Just build a machine aiming at earning money !

Plants vs Zombies like horizontal tower defense games allow you to build this kind of machine. This is Toys vs Nightmares, a nice game. You can buy and build books that produces energy. You need energy to build Toys or other objects. If waves come near books, they can hit and destroy it. That’s why you need to build these machines behind towers. This is a first difficulty : if you build a book on a square, you can’t build a toy !

Of course, you have to define a specific strategy if you want to build this kind of machine !

On Gaia Defense, you sometimes need to build two machines, wait for earning enough money, building new machines, waiting and then building towers. Too bad, you need to wait before being able to build new towers and then shoot against waves.

Machine is just like blocks. If it’s pertinent enough, this kind of machines can be use to slow down waves progression. Waves will either hurt and destroy it or bypass it. Is it interesting to let it destroy by waves ? What about build it, let waves hurt it, repair it ? It depends on your strategy !

Is this post interesting ? Please feel free for giving me your feedback ! Do you know another games in which it is possible to buy some blocks or cash machines ? Please tell me !

Zdefense HD Lite

Zdefense HD Lite is a great mobile Tower Defense game published by chinese studio Zstudio. ZDefense is based on hexagonal squares on which waves walk. The graphic environment is similar to the well-known Hex Defense but also to another mobile games such as Defensoid or Vector Defense. With your finger, you set up some towers on the squares and build a way, the longer as you can of course!, to be able to destroy all the waves. There is a good and easy gameplay. What does this game and another differentiate ? First of all waves are quite intelligent. If you choose to hedge up the smallest way to go to exit, they are able to find another one. Even if they need to teleport and in real time ! I fear teleportation because someone who use it can come dangerously close to exit ! ZDefense HD Lite is a very challenging game ! There are easy, normal and difficult level. But with this game, « Normal » means « Very difficult » ! So be imaginative and patient. Look at this level ! Some waves will come in the same time either from left or right. They will go to the center then go near the exit and you must detsroy it. Not easy, isn’t it ?   Download this game on Android. Free Version – Premium Version

What is a challenging tower defense game ?

Hi guys !

I’m happy to open this blog ! I’m a very big fan of Tower Defense games. I study games ! I enjoy interviewing games developer, talking with researchers about this subject ! And I hope we will share together about these games ! Please feel free to comment my posts, talk about games and so on !

On this blog, I will review TD games I’ve tested and I will analyze the differences between them. I hope I will interest you guys ! So, let’s begin !

Over the past few months, I have played on ZDefense Lite, published by the chinese studio Zstudio. I was just angry not to find the good solution for this level ! I’ve tried 12 times before succeeding !  And if you ask me, i will tell you it is a very challenging game !   His conceptor has previously considered the fact to lose 10 times for each level as normal…

Really ? Are you serious ?
The question is in fact : why and how is it possible to say a game is easy or difficult ?

I’ve made some research on this question. I’ve currently tested about 40 games and it was not easy to find the answer.

Thank to my research, I have succeed in ! The goal of Tower defense games is to find a strategy and test it against waves. If you win, congratulations ! Your strategy is a good one ! But if you lose, you will have to find another one. The more you lose on a given level, the more the game is difficult because you have real difficulties to find a winning strategy !

The beginning of Tower Defense genre has to be found on Warcraft III. In this game, you can find challenging tower defense maps. Challenging ? Yes ! To win, you’ll have to deploy several levels of strategies. And sometimes, you need to think differently.

Labu Games, a studio based in Neo-Zealand, has published on 2013 the excellent games Giants and Dwarves TD ! This is an example of high challenging games. I have to test 5 to 6 times a level to win ! Why ? Simply because on this game you have to fight against big creatures, such as trees, mamooths or Wood horses ! And it’s very difficult to define a strategy allowing you to win against them !

Do you love high challenging TD games ? Ok let’s talk about, according to me, the worst of it ! I’m not able to pass… the first level ! I’m talking about Toys base Defence. This game has been published on 2010 by Fire fly.

 

This game is very difficult. First of all, the design let you think it’s an easy game. Because of toys ! But I assure you this is not the case  🙂

 

Ok then let’s talk about. Have you tested some TD games in which you have lost at least 9 times before succeeding in a level ? Please tell me in comments !

Thanks to Tauxruxbis for his comment !