The world, and lots of squares 

Now I have a very simple building (with built-in collision detection - thanks Unity), it's time to work out how to move around the world, and what I want the game to be like. I think that instead of having it turn-based (like the aforementioned Gollop games), which can end up being remarkably easy to beat any AI at if you move slow enough, I'll focus on realtime but with a nice, big pause button to hand, meaning that the game can effectively be turn-based, but since everything takes a certain amount of time and both the player and AI move at the same time, it should lend itself to a more dynamic game.

This decision then limits the number of player-controller Agents we can have, as we'll need to be able to have direct access over them. I'm thinking 3 or 4 is a good number. Enough to split up if you decide, and enough to work as a group, but not too many as to be unworkable. Preferably you'll become attached to them as well as you play, and be less decisive as to whether to risk them.

To get the game going, I'm starting on Pathfinding. In the above screenshot, the green blocks represent surfaces that can be walked on. For the time being, I'm going to focus on making the world tile-based, as it should lend itself to the less-precise clicks on a tablet screen, and also simplify finding cover and the animations involved in that.