So it's been a few days since my last update, but I'm proud to announce that the design document has been completed! It is a couple of days late, so I will be amending the later design schedule to account for that, but I've already made a few important changes to the game's design. The design document itself is linked at the bottom of the page, but I'll be going over the major changes here as well.
Combat and Upgrade System
When discussing combat in my last post, I mentioned various possible ways the upgrade system could be implemented. After giving it some more thought, the system still seemed too complicated for my liking - having to manage both enemy cores, different types of weapon upgrades, and bombs all at once didn't seem intuitive for an arcade-style shoot-em-up.
The new system described in the document is considerably simpler - players have a secondary fire that can infect enemies, and enemies defeated with it will become wing-men for the player. These wing-men can then be fired back with the bomb button. This still combines the bomb, wing-man, and upgrade systems, but is much easier to understand. In addition, I felt that not allowing the player to directly upgrade their firepower, but instead add enemy firepower to their own, better reflected the theme of invasion the game is based on.
Gameplay Timer
A new game mechanic was introduced while working on my design document - an in-game countdown that the player must manage to stay alive. Players only have a limited amount of energy, but can regain it by infecting strong enemies and defeating chains of weak enemies. While having wing-men can allow the player to more quickly kill enemies, each pair of wing-men also increases the countdown's speed, discouraging them from hoarding them unless they have a plan to utilize them.
I didn't initially plan to implement a timer, but during the concept phase I heard of a game jam being hosted by GameDev.tv. The theme of the jam is "time", so I figured finding a way to implement a new mechanic would help stretch the game's design further. Since it wouldn't change the core design too much, I decided to take up the challenge!
Enemy Classes
At the same time that I simplified the weapon system, I also took a more concrete approach to categorizing the enemies the player will face. They now fall into three distinct classes: Fodder are weak enemies found in groups, Fighters are stronger enemies that can be infected and turned into wing-men, and Carriers which pose the greatest threat, but provide an immense time bonus if infected rather than destroyed.
This design both makes it easier for the player to identify which enemies are priorities and how to interact with them, it also makes programming them easier since each class shares several behaviors. For example, all fodder the player encounters are distinguished only by their flight path, if and how often they fire projectiles, and how fast those projectiles travel.
The Next Steps
From here, the next step will be working on the basic gameplay prototype. This phase of development will last for about 5 days, but by the end of it all player and enemy behavior should be completed! With the exception of the boss at the end, is should be possible to play the first stage from start to end since it has no special stage hazards.
I will be making additional posts here as I continue development. Hopefully by the time I post next, I will have a character controller to show alongside fodder attack behavior! As a final reminder, a more detailed version of my new schedule, along with other gameplay changes and level descriptions, can all be found in the design document below!