SPACE DEFENDER
Teens interested in space
Target group
Game description
Tower-defense game
Type
Player number
Single
'Space defender' is a tower defense game tailored for space lovers and game enthusiasts that combines elements in reality with games. Players will play the role of a space station commander and build a fortress in the vast universe to protect the space station from space debris. There are a large number of props in the game for players to choose and use, with unique game mechanics to bring players a brand new experience.
Inspiration
Game mechanics
Basic mechanics
In “Space defender” player’s goal is to protect the space station from debris. Players can build defensive weapons around the space station to eliminate debris or use thrusters to dodge them.
Core mechanics
Frog of war & Vision
In “Space defender” there is fog of war and defense weapons will not be able to attack enemy if they are outside the field of view, to expand the vision player must upgrade the observation satellite. This mechanic restricted long range weapon in early stage of the game to prevent them from overpower, and force player use other strategy instead of just keep building them. In order to reward players for expanding vision, in late-stage of the game player can spot debris earlier and have more reaction time to doge them, also specific weapons such as lasers will set the attack range according to the size of the vision, which means that if the field of view is large enough, no matter how far the target is, its still in the range. This mechanic also increases the playability of the game in the middle and late stages.
The circle repsent vision range & the dark part repsent frog of war
Grid
In the beginning the station will provide free grids around it for player to use, but soon or later player will find out the grids are not enough for the upcoming enemies. If player want more grids , player must sacrifice a grid to build communication satellite which can add new grids around it. This allows player to determine where to add new grids in a certain degree, compare to traditional tower defense game where all the grids are in fixed position, letting players to decide the position and number of grids can make the game more challenging and unpredictable for player.
Enemy path & Warning
In a traditional tower defense game, enemies normally appear from one direction along a prescribed route However, in the "Space Defender", the enemy has eight possible spawn points. According to the difficulty of the game system will randomly select 2-6 spawn points to generate the enemy. During the preparation phase, before the enemy wave appears game will warn the player where the enemy waves has been generated. This design is to prevent the player from only strengthening the defense in one area, instead player need to allocate resources in different areas reasonably.
The warning stage, the warning sign represents the directions debris are coming from
Dodge
Player can control space station to move in order to avoid debris, each time player operates it will consume fuel. The maximum of fuel is fixed, and to get fuel player need to attack fuel tanks which is very rare in the game, to set it this way because I don’t want player to use this mechanic too much. Adding in this mechanic is to make player feel more engaged in the late game, because when I play other tower defense games specially in the late-stage player can't do much but watching.
Solar panel
Solar panel can provide electricity to 8 grids around it and increase 3 total energy points. For example, in the first picture below the red grids means they are electrified, and player can build weapons that required energy on them.
In the second picture below, two weapons were built on the red grids, because the two weapons cost 3 energy in total and the energy UI shows 3 out of 3 energy points are used, therefore player can’t build more energy required weapons in red grids unless player build another solar to increase energy points.
Communication Satellite
Communication satellite can add grid to the empty space around it. In the picture above the white sphere represents communication satellite, the column and row of grids on the left and bottom are added by this communication satellite.
Observation satellite
Observation satellite can increase the field of view. However, player can’t upgrade it with the resources, only by eliminate a special type of debris can upgrade observation satellite.
Literation
Version 1.0
In the design stage, I added in a button for expanding the vision and the cost is certain amount of resources, soon I relies laser have unlimited range combine with large vision this can easily break the balance of the game， because laser is the most cost-effective weapon in the game, the downside about this weapon is low damage, but after expanding the vision laser can have longer attack time, this makes up for the shortcomings of laser. Therefore, in the version 1.0 I deleted the button for upgrade observation satellite instead I added in a special bonus, when player collect a certain amount of bonus game will automatically upgrade the observation satellite.
Version 2.0
In the previous version the difference between harder levels and easier ones are not much, only difficult levels have more waves and higher enemy health. In order to increase the difference between each level and make it more difficult for players to develop strategies I changed the number and layout of the initial grids. Fewer grids means player have less mistake tolerance; this will test the player’s understanding of the game even more.
Version 3.0
In the last patch I optimized some system in the game. The first is the enemy selection system of the game. Initially I designed to attack random enemies in the field of vision. However, through testing, I found that the weapon's attack efficiency is very low when there are a large number of enemies weapons often attack the enemy that are not threatening, so I changed the enemy selection system to priorities the closest enemy to the space station. After improvement, the efficiency of the weapon has been improved dramatically. Secondly, I found that the balance of the game still needs to be improved, because the addition of various game mechanisms makes the player too restrictive and the difficulty of the game is too high, so I increased the rate of resource acquisition and weapon damage to reduce some of the difficulty.
Programming
Generate gids
Spawn enemies from different direction
Set charged grids
Select the closest enemy in range
Demo
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