One of the notable aspects of this excellent short story is the way that imagery is used so excellently to create a real sense of place and setting. Thus it is that colours are part of this vibrant and riotous description of vegetation and the surrounding landscape towards the beginning of the story. Consider the following description and note how the use of colours appeals to the senses:
The white walls of the verands glared stridently in the sun. The bougainvillea hung about it, purple and magenta, in living balloons. The garden outside was like a tray made of beaten brass, flattened out on the red gravel and the stony soil in all shades of metal--aluminium, tin, copper and brass.
Note how the colours play an important part in painting the scene and evoking the kind of oppressive heat and images that the author uses to describe the setting.
If we have a look later on in the story, we can also see that colours are used to suggest the various conflicts and emotions that characters experience as well. Consider the following description that we are given of the other children when Ravi finally comes out of his hiding place and "wins" the game:
Out on the lawn, the children stopped chanting. They all turned to stare at him in amazement. Their faces were pale and triangular in the dusk. The trees and bushes around them stood inky and sepulchral, spilling long shadows across them.
Note how the paleness of the children and the darkness of the shadows help present the children as ghosts and the surroundings as being tomblike. This of course reinforces the fact that the children are "dead" to Ravi, just as he has been forgotten by them.