Welcome Guest:


MMO Coverage

255 MMOGs and counting...


The Chronicles of Spellborn Developer Journal: Mob Behavior

Posted December 6th, 2007 by Cody Bye

(Editor’s Note: Every so often the developers behind the upcoming fantasy MMOG The Chronicles of Spellborn take a moment to write out what they’ve been working on and the type of gameplay we’ll find in their game. The Ten Ton Hammer staff was fortunate enough to attain their latest dev journal, which focuses entirely on the complex mob behavior found in Spellborn. It’s a fascinating look at developer theory, so please enjoy the article!)

By El “Selachii” Drijver

Although the title might suggest that this is purely an AI related journal, I’m going to stick to the game design side of the subject. Or at least, try to.

I’m also going to try and not just give the situation of Spellborn, but rather talk about possibilities and why I think some choice are good or bad.

Goals

When they were initially creating the mob behavior for Spellborn, the developres came up with the goals of their team.

First some goals must be set, what do we want to achieve when a player fights a non-player (mob). Should the mob fight back or maybe run away in fear? If there is a fight, what should the player experience?

A challenge? Okay, but easier said then done, challenge because? Mob hits hard or mob is hard to hit, mob heals itself or does the mob have a couple friends waiting around the corner? Besides, making something a challenge doesn’t necessarily make it fun. So, the goals will have to be thought through and might evolve a bit during the early stages of the project to achieve the desired ‘vision’ which they all contribute to.

Combining all these goals will actually decide a large portion of the core gameplay so getting them down on (digital) paper is of the essence. Goals should be clear and simple, so everybody can easily understand them, yet they should cover every aspect and leave no questions unanswered.

As an example I will handle a (well known) goal set for Spellborn.

Never should a player be just as effective with his hands in the air as on his mouse, keyboard.

Working with Goals

The mentioned goal sounds pretty easy, but in the world of MMO’s this means that all old fashioned stun/polymorph effects aren’t allowed. We could decide to allow these types of effects and add a counter mechanic, so players have something to do while their avatar is incapacitated. Maybe some button mashing mini-game, popular in a lot of console games currently, to break out of the effect early.

However, we prefer to remedy the cause, rather than the effect, so players will always be able to do something. Slow downs are still present, but no complete root effects. Players might get disarmed but then there’s always magic and the other way around. Another popular mechanic is ‘fear’, our equivalent are the numerous ‘teleporting’ type skills, which displace a target across a short distance, effectively disrupting aim.

In making complex, dynamic monsters, the developers decided that they wanted to advance the current AI found in most MMOGs.

Goals might influence subjects you wouldn’t expect after giving them a quick thought. This goal single-handedly makes sure that big bosses will never be allowed to stun a player to make it harder for the rest of the group, let alone stun entire groups for phase transitions (not counting cut-scenes).

Implementing goals, making them work.

So, we have our complete set of goals, now the game designer will have a good chat with the AI designer. This set of goals will have to be translated to an AI machine which can make choices, which should result in the effects the goals want to achieve…

What if a goal said that the combat experience should be “dynamic and realistic”? Really dangerous terms and they sound like something players will want. Dynamic as in, mobs will pick the weaker target during the fight, make sure there’s no healer in the back, finish off players with low health, ignore players who are good at dodging and so on. Realistic because you want a bear to be a bit slower then a tiger, but have more biting strength. Swords to cut and maces to break bones, but where’s the limit?

I’m sure a couple of you readers now think “cool, yes I want that, of course, who doesn’t”, yet most MMO’s you enjoy work with very transparent aggro systems. Having these complex ‘dynamic’ and ‘realistic’ systems in place, combat could become very chaotic, unpredictable and especially, not a fun player experience at all.

So it needs to be translated to something transparent and somewhat predictable. Players want be able to anticipate moves, create strategies, want to know what kind of reaction(s) they can expect from their actions.

In general, players enjoy it if they can achieve real control over the fight. This doesn’t mean that the behavior should be dead-on like:

-‘hit the mob, get aggro, mob won’t go anywhere else’.

But rather an enhanced version of these simple mechanics. It’s one of those cases where less can indeed be more, in terms of player experience. So, let’s apply that on the above behavior.

-‘hit the mob, get aggro, mob will go to another target if previous target keeps being healed’.

According to El, fights should only be predictable on  a basic level.

Although this is ‘dynamic’, it’s far from the poohah-dynamic AI you read so much about on game box covers and feature lists, but will in fact add a great deal of gameplay. Let’s add another little simple rule.

-‘hit mob, mob checks which nearby target is the weakest and aggro’s, mob will go to another target if previous target keeps being healed’.

Simple additions which can already cause countless of ‘dynamic’ combat situations. Because these rules are rather basic, players will be able to predict the behavior after a couple of encounters, so they can be expanded with more of these basic rules. Some designers prefer to add chances here and although I think some use of ‘chance’ can make the experience a lot better, excess use of it will make the fight chaotic and eventually destroy the fun all together.

So, should fights be predictable? The basics, yes, to a certain level, even though it makes the situation not so super-dynamic-high-realism. It will create a better, more manageable user experience and players will be able to estimate what can happen…to a certain level.

This subject is far from covered completely, but I’m going to close this journal now. I hope my message came across and maybe even sparked some interest. I’m open to well constructed questions and opinions, which I might answer or reflect upon in a following journal.


Does mob behavior need to advance to continue the evolution of MMO gaming? Or are you content with the way mobs act in current games? Let us know on the forums!

Ten Ton Hammer is your unofficial source for The Chronicles of Spellborn news and articles!



The Chronicles of Spellborn Details

    Windows
  • Developer: Spellborn NV
  • Genre: High Fantasy
  • Status: Open Beta
  • Official Website
  • Official Forums
  • Retail Price: Free Client Download
  • Monthly Fee: None (Premium Account available)
  • Release Date: December 5, 2008
  • ESRB Rating: Not Rated

More on Ten Ton Hammer