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% replaces any number of letters (la% - lake, lamp)_ replaces one letter (ca_ - car, cat)

Crossword clues for Foil, as a plan 6 letters:

THWART: Foil the plans of
GOAWRY: Get foiled, as plans
DERAIL: Foil, as a plan
BEAHERO: Foil the villain's plan, say