More AI Improvements

Since the last article on the robot AI, the robots have had another round of work. They now hear your ship, the whole mine slowly grows suspicious of you, and the higher the difficulty level, the more they think ahead. Here is how the robot AI works as a whole now.

Senses

Robots only see what is in front of them, and they need a moment to react. Your headlight gives you away only to the robots it shines on.

They hear your engine when you are close and turn straight towards you, even when you come up behind them. The afterburner is loud, while the cloak makes you almost silent. They also hear shots, impacts and fights, they know which direction a shot came from, and a shot flying past wakes them up.

A robot that has not seen you, heard you or been told about you does not know where you are. Robots remember where they last saw or heard you and go there, not to where you really are.

Fighting

Robots keep their preferred distance from you, strafe, and change direction when they are hit. On the higher levels they back off while reloading. They always lead their shots, and how well they aim depends on the difficulty level. They only fire blindly at a spot where they have just seen or heard you. A badly damaged robot may retreat to cover and come back later, and when robots lose sight of you, they chase you for a while before they give up.

Moving Around

Robots take real routes through the level and spread out in corridors instead of flying in single file. Idle robots look around or wander about instead of just hanging in the air.

Teamwork

Robots that spot you report it by radio, and others come to check. Only a few set out at a time, and no more come once enough of them are near the spot already. Robots close to each other stay out of each other's way and come at you from different directions. Brain robots keep everyone around them on the radio and send out small squads: one rushes you, one flanks you, one snipes.

The Mine Remembers

Every sighting, every hit and every kill makes the mine more suspicious. The alarm then lasts longer, robots come from farther away, and they keep searching for longer. The suspicion fades slowly while you keep quiet. Robots that arrive and don't find you search the area and then fly back to their posts.

Thinking Ahead

The higher the difficulty level, the more the robots plan. They try to cut you off where you are heading. When they hear you coming, they may lie in wait beside a doorway. Once the mine is suspicious enough, they guard the passages to the exit, the reactor or the keys. From Ace up, a robot that hears a comrade die calls in the spot, waits briefly for backup, and then the group comes looking for you together.

All of this scales over the six difficulty levels, from Trainee to Braindead. On the low levels the robots are slow, deaf and forgetful. On the high ones they work together, but they still play fair: no eyes in the back of their heads, and no knowing where you are without a reason.