Bounce (level design)

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A symbolic diagram of a bounce.

A bounce is a layout element beginning with an inaccessible area, forcing the player to sidetrack and remove the obstacle before proceeding. In some ways, it is similar to a loop. Most bounces begin in a room with an obstacle (locked door, force field, etc) and lead to an event that destroys this obstacle (disaster sequence, physics puzzle, button pushing), thus allowing the player to backtrack and proceed past the removed obstacle (unlocked door, deactivated forcefield).

Use bounces to emphasize certain plot events or gameplay elements. Always look at the "big picture" and analyze the bounce's function in context to a level's overall pacing.


In terms of resources, bounces are incredibly efficient. The same areas are being used twice. The player is literally backtracking through previous rooms, which generally translates into less work for the designer.


Use of the same environment allows for effective guidance of the player. Since the player has already explored the area before, it is assumed that the player will partially remember the room structure and which exits. Also, it is technically impossible for the player to get lost.

Ease of Use

Bounces vary in complexity. Simple bounces involve the player fighting through rooms of monsters to activate a keypad. More intricate bounces incorporate multiple areas or objectives. Nonetheless, bounces generally require less work on the part of the designer, but more effort from the player.


Unlike a loop, bounces possess no illusion of choice. The player sidetracks and returns - he is aware of his position in relation to the rest of the level. If nothing interesting happens on the return trip and it is not obvious what has happened, then, especially if it is of length, this will stick out as very badly implemented backtracking to a lot of players. To solve this problem, try making the change obvious (E.G. a video screen showing a door opening) with an immediate effect on the player (E.G. hostile soldiers attacking the player through the open door). Players don't mind backtracking when the goal seems clear or purposeful, and the trek is not overly long.

Other times, a bounce simply isn't appropriate. The player is essentially travelling in a circle and his sense of progress is diminished. During the Water Hazard and Highway 17 chapters of Half-Life 2, most bounces were either optional or short - a long extended bounce would have disrupted the focus on sheer distance and travel.


In general, a bounce is much simpler to implement than a loop, but can still be effective. Here are some notable examples:

Anomalous Materials / Unforeseen Consequences (Goldsource)

Anomalous Materials diagram

This bounce is used for dramatic effect, primarily to emphasize the contrast between the pre-disaster and the post-disaster Black Mesa. When the player initially arrives, he is greeted by friendly NPCs and playfully chastised for being late to work again. After the resonance cascade, the player's former colleagues have mutated into zombies; dead bodies and wreckage are strewn about the level; the lighting is noticeably darker. The player comprehends the "unforeseen consequences" of his actions.

From a design perspective, this bounce at the beginning of Half-Life is very effective. Although the player is given very little direction after the resonance cascade, the player still manages to find his way through the ruined labs and up to the office complex. The player's familiarity with the labs helps the player navigate, and also serves to empower the player: he is not relying on an objective list displayed on the HUD to progress through the level, but rather he is relying on his own memory of the level layout as he initially explored.

Power Struggle (Goldsource)

To do: more detail In this level, the player has to drain a pool of coolant, go into it, rearrange the barrels, re-fill the pool, and cross on the rearranged barrels.

Route Kanal (Source)

Route kanal bounce 1.jpg
This is is a good example of a Bounce map.

In Route Kanal, there is a scene where the Combine cut the player's escape by closing a water lock. The player must leave the airboat, fight through a small Combine outpost, blow up a couple of flammable barrels thereby breaking open the canal doors (seen in the picture on the right), then backtrack to the airboat and proceed through.

This is the most simple type of Bounce map you can create. Its task is to hold up the player's advancement and divert him/her to a nearby location for him/her to be able to proceed further into the game.

Highway 17 (Source)

Bridge pano.jpg

In Highway 17, the famous bridge scene is a perfect example of a Bounce mission. The player must fight off a Combine drop team and a number of poison headcrab zombies, only to discover that the way onwards is blocked by a force field. To disable it, the buggy must be left behind and the player has to climb his/her way beneath the bridge to the other side and push a button in a control room. Then, on the way back, a Combine gunship must be fought off, after which the player can proceed through the force field.

Metastasis 1 (Source)

To do: diagram, description The player must descend into an underground bunker area, press a button to open the Combine gates, then return to the surface and proceed to the center of the island.