Artificial intelligence in Wakfu

What is AI used for?

AI serves to bring Wakfu's creatures to life when they fight. Without it, creatures would not be able to fight at all and the ecosystem wouldn't function. The AI server governs the choices creatures make, giving each of them a personality of their own.

How does AI work?

Behaviour profile

What we call a 'behaviour profile' is at the root of all the decisions the monsters make in combat. When the AI server calculates the different options open to a creature, and comes up with 2 'equal' possibilities, the server will always choose the action that corresponds most to the creature's profile.

Every creature has the following type of behaviour profile:

• Aggressive
• Long-range combat
• Support
• Healing
• Retreat
• Kamikaze (seeks out traps)
• Etc.

We can create as many of these profiles as we need, but we also need to take into consideration the fact that the conditions of combat can evolve and change! For this reason, a creature which is aggressive at the beginning of a fight may end the fight being passive.

Decision guides

Decision guides are added to each creature's behaviour profile so as to avoid predictable actions and/or prevent combat becoming impossible. These guides apply rules to the behaviour of creatures in combat.

For example, if a creature has a very powerful spell we will limit its use to one in every ten turns rather than every single turn so as to make the creature's behaviour less predictable. Although the AI server would normally direct the creature to use the most powerful spell available, the decision guide will force it to choose a different attack.

This way of influencing decision-making is very important, particularly in dungeons because it brings a more cinematic element to the gameplay. The series of creatures and rooms the players encounter is designed to be an unforgettable experience, and not just a pre-programmed succession of identical fights.

We hope that our AI engine will offer players more exciting battles in Wakfu's underground chambers, where every step of the way will bring a unique confrontation.

Practical running

This is the practical description of how AI runs during a fight.

• 1 AI attacks.
• 2 It takes into consideration all the features of both the creature and the fight: behaviour profile, spells, enemies, allies, environment...
• 3 It simulates all possible strategies and memorises each scenario. AI is a very powerful element and can test hundreds of thousands of possibilities with each action! When simulating, AI also takes into consideration the opportunities to hurt its allies if this means victory! Every single possibility is assessed.
• 4 The AI compares the different scenarios and chooses the action with the highest rating.
• 5 If all the actions have a bad rating, then a default action is taken. This way, AI is prevented from thinking and making the players wait for too long.

AI in practice

Moral dilemma

"In a fight, a creature can attack an ally creature if it's a good move for its combat strategy."

This is an easy action for a human being to take, but a lot more difficult for AI which usually tries to optimize the fight and protect its allies.

How does AI select actions that won't directly affect Health Points? For instance, for a spell which "pushes" its target, the "depth" will be taken into consideration in the choice of action to be taken. This calculation allows AI to evaluate the direct consequences of the action, based on several levels of consequences.

The creature eventually realises that sacrifying this little ally creature next to a player that will be killed in the action will also deal great damage to the player before they die too.

Wakfu AI's Future

Communication between creatures

In the coming evolutions, we wish to implement a system of communication between creatures in fight. The objective is to create group strategies by letting creatures communicate and give instructions to each other.

Let's say you have 1 Gobball Warchief and 2 Gobballs. If the Gobball Warchief gives the order to attack player n°1 instead of player n°2, the two Gobballs must obey and attack player n°1. However, if one of the 2 Gobballs gives the order to attack player n°2 instead of player n°1, the Gobball Warchief will ignore such an order and there's a poor chance that the second Gobball will listen and obey.

But even when the Gobball Warchief gives the order, there's always a possibility that a creature will choose not to obey, according to its behaviour profile.

Whatever the case, it will offer a new strategic dimension to combat since players will now fight against creatures that can develop strategies as diverse as they are unpredictable.

Behaviour change

To make Wakfu even more unpredictable and therefore more interesting, a creature's AI profile can be changed in fight.

For instance, an Osamodas has a series of spells to give orders to their creatures: attack this target, protect, heal, etc. No matter what its profile, the creature will obey. At each spell, the creature's behaviour will change.

A Boowolf is naturally aggressive and even if it is ordered to protect something its basic aggressive instinct must be kept!