What Makes a Good Mod? Simple Answer…Fun!

Modding & Development Source

My name is Jim Partridge and I’m a modder primarily for Half-Life 2. My previous work includes Half-Life 2: Deep Down, Half-Life 2: Daylight and numerous PlanetPhillip competition entries. I decided to join LambdaGeneration this year as a contributor for the site’s Modding & Development section. My primary interest is in level design with a focus on gameplay, I’m a gameplay nerd in fact… Join me in my nerdiness!

What Makes a Good Mod? Simple Answer…Fun!

The Half-Life 2 community is very lucky in lots of ways. Ten years after the original game was released, we are still seeing quality single player maps and mods being produced on a very regular basis. There’s not many other titles out there that can claim that.

The quality of a mod is a very subjective thing. Take a look at many reviews on ModDB or PlanetPhillip and you’ll see players homing in on a variety of elements from ‘look and feel’ to the lack of custom content or frustrations with a new control mechanisms. There is one thing however that can determine a mod’s success or not and that can be captured in one sentence. Is it fun to play?

Finding the fun

Some may argue that “fun” itself is a subjective concept. What one person finds fun, another won’t. I disagree. Fun in a game can be defined in very simple terms. The ability of the game to vary it’s outcomes depending on the player’s choices. The fun is the player learning and adapting their approach to a given scenario in order to see what effect it will have on the world. This is the reason why the Team Fortress and Counter-Strike series are so popular and why players are willing to re-engage the same scenario over and over again. The players tactics in the last round got their head blown off in less than ten seconds so this time they’ll try something different and eventually, they’ll find success.

Single player level design is no different and the Half-Life games give mod makers a whole selection of challenging foes, weapons and physics objects that can be combined to create complex scenarios offering countless outcomes.

So with this in mind, it’s often amazing to me how many single player mods miss the mark with regards to the fun factor. You can build all the custom assets, custom characters and fancy architecture you like but if your mod isn’t fun, you’ve stumbled at the first hurdle. It’s also important to note that fun isn’t necessarily tied to difficulty. Just adding more bad guys to shoot doesn’t up the fun factor unfortunately, especially when no time has been spent on getting the bad guys to act intelligently. Personally, if I get stuck in a mod due to the odds being almost impossible to beat, I get bored very quickly. I’m far more interested in a mod that allows me to alter my tactics and try different methods of attack, many of which could be successful. A mod that allows only one solution to a scenario isn’t much fun at all.


The nice thing is that designing a mod or map to be fun is probably the least challenging part of the design process. Level designers don’t need to worry about what anything looks or sounds like. In Hammer, just slap a few simple shaped blocks together to provide elevation or cover, throw in some NPC’s, some AI nodes, turn on the Cordon tool and compile. Easy peasy… Then you tweak. You tweak and play in a cycle, discovering new NPC AI behaviors as you go until you have an encounter that you are happy to play over and over again. It’s a good rule of thumb that if you are happy to play through it over and over, a player will enjoy their first play through (and possibly come back for more). Play testing will of course reveal if you were misguided or not and is also an important part of development but the process of evolving fun game play can be very rewarding.

Even if you’ve never opened the Hammer Editor, you can probably build a fun encounter in less than an hour using the method above.

Why not have a try and share your map among your friends or on Garry’s Mod.

What isn’t fun

Here’s my list of sins a mod can commit that fall into my non-fun bucket:

  • Offering a puzzle we’ve all played before
    Oh dear god I don’t want to find any more stupid batteries or cog handles.
  • Forcing the player to listen to very long exposition or instructions
    If you can’t explain it in less than 10 words then rethink.
  • Putting combat in a puzzle area
    Get these fricken Ant-Lions off my ass while try to jump this gorge.
  • Having bad guys with guns that just run directly at you
    …and start hitting you with their rifle butt.
  • Telling the player exactly what to do
    There’s no fun in following explicit instructions.
  • Not directing the player properly
    The moment the player starts hitting the walls with the crowbar you’ve failed as a level designer.
  • Spawning bad guys behind the player
    I just cleared that fricken room!
  • Pixel Perfect Jumping
    A handrail is not an acceptable jump puzzle surface!!
  • Pixel Perfect Shooting
    That guy is like 100 miles away!!!
  • Characters with boring names
    Hi! I’m Gavin! The resistance fighter!

… and I’m sure I could find many more.

Before anyone says it, yes, you’ll probably find some examples of the above sins in some of my own work from the past, but no doubt us modders learn as we go on and always try to improve.

What are your greatest sins in mods? Let us know in the comments below!


  1. Maps that don’t work anymore

  2. Great article Jim,

    Personally I hate mods which just place random HL2 NPCs everywhere without any context or story.

  3. I really enjoyed the article, but I’d like to point out something interesting. “Having bad guys with guns that just run directly at you.” I know what you mean by this Jim: having enemies that JUST do that can be un-fun, but if used correctly enemies that don’t have a sense of self-preservation can provide an interesting choice. Examples: “Do I shoot the fast zombie or the high-health zombine behind him?” “Do I run away from the grenade or shotgun the AR2 elite rushing me?” I know you probably already know this, I was just pointing it out to clarify it for others.

    • It’s true. I’m not saying they should never show that behaviour (although I would do everything to avoid it in my maps), but as you say it should be their last resort when the player has reached them.
      The fast zombie is designed to come directly for you which is the reason why I specified “bad guys with guns”.

      Combine Soldiers work best at a middle distance and should only run directly for the player when they have no further cover options remaining for them in my opinion.

      I often separate the player from using fences or drops so that the Combine have no other option but to use the cover around them. It makes for much more engaging game play.