I’ve been playing a lot of Battlefield: Bad Company 2 lately. I confess a massive obsession with team-based multiplayer FPSes. Battlefield I have a love/hate relationship with, but that’s for another time and post, perhaps. Today I discuss something that has occurred to me over my last few plays, and in thinking about it, it’s a fascinating instance of level design effected by game features.
Destructible terrain poses some interesting level design challenges, as well as provides some interesting options to the player. How so? Well, read on:
The Run-Down on Breaking Things Down
So, aside from the obvious, what’s so interesting about blowing stuff up? A fair question—after all, the obvious is that it’s exciting and visceral for the player, and while that’s quite a bit to excite a designer, it’s not really the focus today.
Instead, the interest lies in how the destructible objects alter the level balance and flow in a multiplayer game setting. To the left is an example of the beginning state of the approach to a pair of capture points in one of BC2’s maps (Port Valdez in specific). This one is a very good example. Items of primary note are the tree-covered slope dead center. These trees effectively obscure a road and a hill which form a primary line of advance for the attacking team from their initial spawn to the first two points, giving the attacking team cover to approach and fire from on their way towards the points. Also of note are the buildings barely in the left side of the frame, which form good cover for defenders to fire from, and the fence surrounding one of the capture points (just beneath center).
The benefits of this cover should be pretty obvious—snipers have cover to fire on without getting counter-sniped, other attackers and defenders have places to hide from the snipers and each other, etcetera. All the typical benefits of using cover, basically.
So to the right, we have the same area after some judicious explosives and high-caliber rounds have had their say in the matter. It’s a wholly different story: the trees are cleared, opening up the road and slope bare to defender fire; holes mar the fence and buildings, one of which has collapsed entirely, likely taking anyone inside with it. Like the attackers, the defenders are also more exposed, though perhaps not as badly so.
With the change in scenery comes changes in the balance of power between the sides. The defenders now have a marked increase in ability to spot and remove incoming threats, making the attackers’ job much harder to take on.
So? What’s the Point Here?
The point is, this produces a design concern that level designers must take into account, and also produces a wildly varying map dynamic depending on player actions(which are largely out of the designer’s control). This also produces some practical balance issues that a player would do well to keep in mind.
We’ll start with the player perspective. it behooves a smart defender to destroy as much approach cover as they can at the beginning of a round. The natural tendency in a round is for much of this cover to get destroyed eventually anyway, but since the defenders’ win condition is a matter of wearing down the opponent until attrition depletes the team’s tickets while still controlling the capture points, it is smartest to remove as much of the cover keeping the other side hidden as possible as soon as possible. For the attacker, the smart move is to move and take the objectives as fast as possible while they still have advantage of covered approaches.
The concern for the designer is somewhat trickier. After all, a player only has to worry about pushing the balance in favor of their own team, but a designer must carefully balance teams to produce a compelling game experience. The effects of environment destruction are a challenge, then, because they produce a positive feedback loop—that is, the tendency is for a team that’s managing to do better to slowly have an easier time continuing to to well.
In the attackers’ case, maintaining momentum in taking objectives makes it easier to continue to do so. This is partially due to successful capture of an objective pair scattering the defending team as the spawn points shift, and also due to continued enjoyment of large amounts of cover, and the defenders not having time to get set up to defend.
On the defenders’ side, the primary cause is the cover. As a battle gets protracted, the amount of cover gets smaller and smaller, making the job of defense easier. Additionally, past an initial short window, the defenders are prepared for the incoming attacks, which improve their ability to defend. A successful defense tends to become increasingly successful, on the whole.
The designers at DICE appear to have handled this problem in several ways.
One is through underlying game design: the valid map area expands after a point pair are captured, opening up the area the next pair are in. This happens for defenders immediately upon losing both points; attackers must wait a period of time before they are allowed to enter the new area.
Another way they’ve handled it is to put a boundary on the amount of cover that can be destroyed. Indestructible cover is fewer and farther between, usually, but it exists, and defines a minimum boundary for the ability to hide from enemy fire. Back in our example above, there are rock formations at the top and bottom of the tree-covered slope. These provide permanent cover locations, which provide guaranteed cover from (most) fire from defenders, though not nearly as effectively as the forest does at the beginning of the round. Similarly, defenders are typically given a few walls or buildings that are hardened construction or otherwise do not break when hit, providing similar bounds.
It would be really interesting to see how the level designers at DICE chose the mix of destructible objects and indestructible. It certainly makes for a fascinating twist on multiplayer map design, though unfortunately it’s pretty likely that the community(and myself) won’t be getting a chance to try it out. As far as I know, Battlefield games have rarely released editors. But that’s a gripe for another time.