Pretty much everyone knows that "exploit" is a dirty word. An exploit in an MMOG is anything that lets you work outside of the established rules of the game to do something that you couldn't normally do, usually in a way that lets you bypass or defeat content more easily than you're supposed to be able to. Finding a way to jump the fence before Arathi Basin actually starts is an exploit. Purposely glitching trash mobs into walls so that you can walk past them to a raid boss is an exploit. Killing a monster from a position where they're totally unable to hurt you is an exploit. In PvP gameplay, exploits are the kiss of death -- they break the game and make things totally unfun, because one player is cheating at the game.
But is that necessarily the case for PvE gameplay? I'm not so sure. The commonest way to avoid players using exploits to kill monsters is that when a monster decides that a player is jerking it around too much (and is able to damage it without being hurt themselves), the monster just starts evading and goes back to its starting point. It's the virtual NPC equivalent of saying, "Fine, you don't want to play fair? I'm going home." But that mechanic misses an important consideration -- it's kind of fun to find and use ways to exploit mobs.
I'm not saying that designers shouldn't fix exploits or that exploits aren't harmful to gameplay. I am saying that when you find a "clever" or "original" way to kill a monster, it's kind of a thrill. Is it so bad to allow that once in a while? Take kiting, quad kiting, and fear kiting, for example. None of those mechanics are nearly as prevalent in modern games as they were in EverQuest. However, they were pretty fun. I highly doubt whether the designers really planned all of the various soloing techniques players figured out how to use from the very start. I'd wager that a number of them were invented by creative players smashing mechanics together.
Similarly, pathing bugs can offer some interesting ways to kill monsters that should be too hard for you. Hop on the log, the monster goes running around to the other side while you feather it with arrows. Hop off the log just before it reaches you, and it goes running back around to the first side. Rinse and repeat. I had a lot of fun in a solo Age of Conan mission this weekend where I jumped onto a high ledge where melee mobs couldn't reach me and killed their casters with arrows (the melee ones just evaded when I tried to shoot them).
While doing stuff like that all the time would probably ruin the fun of the game, it's a blast to find and use those kind of techniques once in a while. What exactly makes it so entertaining to use exploits like these? Well, they often take some skill to pull off. Maybe getting to that archery ledge takes an extra tricky jump, and the log hopping trick might require some precise timing. Also, they aren't immediately obvious, usually. Unless you read about them in a forum or something, you often find exploits totally by accident. Even if you do read about them it's like possessing some secret and arcane knowledge about the game.
It's probably also worthwhile to think about what a game is. If you consider that almost all games consist of being presented with a series of rules that you have to work within to solve a challenge (pretty much the definition of a puzzle), that's almost exactly what finding and using an exploit is. While you're not solving the challenge in the spirit of the rules, you are solving the challenge within the physical rules of the game world. It's like flipping over a wall in Mario Kart, teleporting through levels with Nightcrawler, or killing Rocksteady by hitting him with Donatello over some crates -- while it's cheating, it might still be fun for you.
However, designers can't be expected to leave exploits in games just because it might be fun for some players. Especially given the social nature of MMOGs, it's simply not fair for some players to be able to use exploits that allow them to easily kill NPCs while others can't, and it makes content trivial that shouldn't be. Exploits aren't nearly as game-breaking in PvE as they are in PvP, but they're still problematic for any number of reasons. So, how exactly do you keep the fun-factor that's associated with killing enemies in unique and original ways without allowing exploits to run rampant?
I think the solution is pretty obvious: Let players kill NPCs in unique and original ways, and have them react accordingly. While it's probably far more difficult to design for, I'd love to see some out-of-the-box design thinking that let creative players slaughter their foes in more ways than "stand and trade blows" until one of us dies. Oblivion is a good example of this. There were lots of traps in the game, and if you could get an enemy to chase you through a trap, you could often turn the trap to your advantage and have it kill them instead. I'd also like to see options for tricking NPCs into following you up onto a ledge and then pushing them off to fall to their doom, or actually being able to stand on a high vantage point and kill NPCs who can't reach you. Do they have to just evade? Can't they run for cover, or pull their own bow out, or call some ranged friends before they die? All of those would be interesting ways to defeat your opponents, and give you a chance to break up the monotony of fighting.
City of Heroes is a game that lets you make use of similar mechanics. While knocking your opponents off rooftops won't kill them, it does force them to climb back up while you deal with their friends. It's that kind of environmental interaction that makes games feel more alive and adds an extra level of strategy and planning to combat. Exploits are often about using your environment in a way that's advantageous to you -- why not plan in it as part of the game? Honestly, I wouldn't be surprised if interactive environments that are actively used in combat ended up as a major advancement in MMOG design that could really shake up the massive genre and show us a new way to play.
Isn't it about time that we got away from the same formulaic idea of combat (I whack you and you whack me until someone dies) that's been around since MUDs were cool?
