I'm in the process of developing a flash Tower Defense with a sci-fi/retro theme. I thought that the old fashioned "Kill monster, get gold, build tower, upgrade, repeat." was a bit too simple and decided to add a few mechanics to make it more interesting/unique.

However, after I had mapped out the mechanics I began to worry that it may be a little too complicated for the average game player.

Let me give you a small run down of the mechanics I added:

There are two resources "Energy and Matter". Matter is like traditional "Gold" where the player spends it to build towers, buy upgrades, etc. Energy, however, is a resource used up by towers, and is obtained primarily from energy support towers. Every time a tower shoots it will consume a fixed amount of energy.

When the player uses up all his energy due to having too many towers firing off at a time the game will initiate a "black out" which keep all towers from firing for 5 seconds. This makes it extremely important to maintain your energy towers output with your towers' upkeep adding to the strategy required.

I've also made a few special towers that use mechanics that might be a little confusing:

Nuclear fusion/fission centers. These allow you to convert Energy to Matter (Fusion) and Matter to Energy (Fission)

Wormhole. This set of towers will be a one way portal on the map. What will happen is when the player selects to build a wormhole they will be prompted to place first an entrance and then an exit. When enemies are placed within range of the exit portal the entrance portal will be targeted by the towers near it and will be shot as if it were an an enemy. As the entrance is shot the exit will duplicate the bullets and direct them towards the enemy.


And finally (sorry for the long post) my tech-tree works a little bit differently.

The tech tree is based on combining towers and requires that the previous towers be the same level as the higher tech one.

For example:
A Black Hole tower requires a Gravity tower and a Nova tower. So to upgrade a Black Hole tower to level 3 you would need both a level 3 Nova and level 3 Gravity. And since a Nova tower requires a Fire and Energy the total requirements would be Fire, Energy, Nova, Gravity, all level 3 in order to upgrade a Black Hole to level 3.


That's everything, please tell me: do you think these mechanics will add to the game play or are they just going to confuse the hell out of people. Thanks!

I thought about the energy idea, and while it seems kind of interesting, I think it would be a more interesting idea to work with 'positive reinforcement' instead of 'negative reinforcement'. Essentially when you're requiring all towers to use energy to fire, you're just assigning them a second hidden resource that is difficult to estimate. It seems to be 'more complex' but I don't necessarily think 'more fun'.

Via this game mechanic the 'best' build would also be the most frustrating, as you'd reward players for keeping the bare minimum amount of energy needed to fire, while this also has the greatest risk of blackout. I'm sort of imagining the blackout to be pretty much 'instant lose' or rather 'instant quickload' (who could survive without any towers for 5 seconds in any heated TD game?).

Maybe consider instead of requiring towers to fire at all, you could store up energy to allow them to 'hypermode' and triple their firing rate? This would allow you to keep your energy mechanic without the frustration inducing watching your total power fluctuate between 0 and 1% just waiting for everything to fail. This rewards the player with some extra carnage (usually enjoyed in a TD game), plus has a more strategic element than what you're suggesting. If you allow a bonus for having energy then the player can choose the amount of energy production he wants to use with instead of just being forced to do so or lose.

I guess I'm just thinking that your penalty is too harsh, and if you are going to introduce that mechanic at least make it a trade off (should I build more energy or towers for maximum efficiency) instead of a 'build this or you lose', cause then it just seems like a chore.

I hear your criticism and I had considered it as well. I was thinking about reducing the penalty (The funny thing is when I first thought of it I was entertaining the idea of 10 seconds LOL).

(just a side note not all towers require energy, in fact there's a tower that will produce energy every time it fires.)

I also thought about energy being solely a negative aspect of the game. That's why I created the nuclear fusion towers. Say that you created an excess of energy towers early on while maintaining an efficient tower setup. Once you unlocked The fusion tower you could turn your excess energy into matter allowing you to buy upgrades/extra towers much easier due to the risk/planning you did during the early game.

I do like the idea of special attacks / power mode though. I just need to figure out a way to implement it that is balanced/interesting.

I see the Energy idea as just a way of hindering the player, if their guns are set to automatic firing then they're just going to deplete their reserves and will be hit by the penalty. I think karwosts suggestion of using energy for an improved state would be better.

The idea was to balance their offensive towers with their energy towers.

Energy is a resource and by its nature it does hinder the player who doesn't have it, the same way not having gold or other resources would hinder a player.

For example: An energy tower level 2 will produce 4 Energy per second, while a particle accelerator tower will shoot every second using up 1 energy. Therefore 1 energy tower can support 4 particle accelerator towers while creating a surplus of energy between waves.

It is a hindrance but I don't see how frustrating it would be to just build another energy tower and keep the balance between intake and upkeep. It forces a player to focus on efficiency rather than brute force.



I think there was a problem explaining the mechanics of the energy tower which is an extremely important part of the strategy. Both of you explained running out of energy like the player would have no power over the amount of energy they were receiving and were doomed to run out despite their efforts. So let me clarify:

The Energy tower will provide the player with energy over time, and is the cheapest tower to build. A player must place one at the beginning of the game in order to begin receiving energy and place other towers.

The algorithm for energy output is E/Second = Lv^2 With a maximum level of 5. So a level 1 tower will give 1 energy per second while a level 5 will give 25 ( as opposed to the inexact/"hidden" percentage implied by karwosts) This number would be exact, readable, and calculable.

I also included the fusion tower for the very purpose of positive use of energy, to create extra resources for taking the risk of investing more matter in energy towers while neglecting the offensive towers.

[Edited by - AfroChrist on September 20, 2010 7:16:16 AM]

First, have you ever played desktop defense? Its one of the better tower-defense games IMO.

Anyways, I think your ideas seem pretty cool. For the 'energy' concept, I'd consider using something similar to a pylon in starcraft. You can set up a pylon that gives x amount of energy to the towers around it, and you can only put defensive towers near a pylon. The pylon would be upgradeable, and would regenerate energy at a fixed rate. If the towers inside the field used more energy than the pylon could generate, they'd black out. This would force users to upgrade their pylons, and would add a nice level of depth to the game.

Ofc I've played desktop defense before, how could I develop a defense game in flash without at least playing that game lol. One of my favorites as well.

I've never played SC1 (and SC2 I've only played as Terran) but the Pylon system system sounds exactly like what I'm talking about except with a shared resource pool, not localized.

I'm thinking about the idea of localized effects, that would cost energy, but I think I'll keep the shared resource for now.

Try The Space Game. It has a similar energy concept. I didn't think it added much to the game, except frustration. You were either out of energy and unable to defend your base or drowning in energy and unsure what to do with it.

If the player can directly use energy to create various effects, then it will become interesting. Spend X energy to increase attack speed of a group of towers for 15 seconds, Y energy to create a mini black hole damaging enemies, etc. The player will have an incentive to watch their energy budget and gameplay depth will be created.

Speaking of ideas relative to this, you could also have a 'hyper' mode in which towers use 50% more energy, but deal 25% additional damage for a short duration. This may help prevent the 'drowning in energy' situation the above poster mentioned.

PS. PM

Like others have pointed out, the energy system as designed is negative reinforcement, which is likely to put off players. Instead of focusing on energy for the purpose of attacks, why not apply the energy mechanic to the other aspects of defense games. Rather than requiring energy for attacks, how about requiring energy for upgrades? You could even avoid explicitly requiring energy but allow more upgrades or attack types based on collected energy. This also has the added bonus of letting you focus on basic mechanics on the first few levels, and then easing players into the more complicated mechanics.