The life force was a combined clock and progress meter used to track the energy status of the dungeoneer (the main contestant). It could be reduced by the dungeoneer taking too long (Treguard would often tell the team "You're wasting Life Force"), taking "damage" through being attacked by monsters or obstacles, taking the wrong route or making bad decisions. However, it could be refuelled by placing food in the knapsack.
In the first five series, the life force was a computer animated image of an adventurer wearing a helmet. When healthy the image was complete, it would be shown against a Green background. As life force was lost the background would turn Amber and parts of the helmet would break off into pieces. Once the helmet was gone completely, pieces of skin would break off to reveal a skull underneath (though no blood was seen), now with a red background. If life force diminished further the skull would start to crumble away, ending with the eyes rolling away past the camera as a death knell tolled.
In series six and seven, the life force was a picture of a walking knight losing armour to gradually reveal the skeleton which eventually crumbled to bits.
In the final series, the life force was a picture of an animated pie, its slices slowly dissolving. This particular life force only appeared whenever the dungeoneer picked up food.
The Dungeoneer's "death" was indicated by the life force sequence ending, either by the second eye rolling off-screen or the skeleton collapsing (though the latter was rarely used). Unlike the first two sequences, the "pie" life force was never used to indicate a death. Also, Team 3's death in Series 2 never used the death sequence.
During filming, the life force animation was never shown on the adviser's screen (it was only shown on the audience's viewpoint), although changes to its status were announced by Treguard (e.g. "Life Force damaged!"). No dungeoneer ever died due to their life force simply running out - there was always an additional factor that caused the death.
Certain traps and pits would cause instant death, regardless of remaining life force. For example, if the dungeoneer stepped off the edge of a platform, they would "fall to their death". Occasionally, the dungeoneer's death would be animated. The most common death showed the challenger falling straight downwards while waving his arms. If he comes in contact with a moving saw, sometimes it would appear that the dungeoneer got split into two pieces. These animations were made in post-production.
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