A token sink can be a useful counter-play to an opponent's use of a holding station; holding stations are generally capable of storing an even larger stack of active tokens, while extracting tokens from a token sink frequently consumes more tokens than are released.
The tactical possibilities of using a token sink to bog down an opponent's use of Throgmorton's Hydra or to enhance the effects of a hostile frume should be readily apparent to most players.
The Fronsky diagram symbol for a token sink containing retrievable tokens is an underlined triangle with vertex pointing downwards. Empty token sinks of varying sizes are implicit to most stations and are not generally marked.
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