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All answers having "Er-r" as clue:

3 Character Answers:

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SIN

UMM



4 Character Answers:

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FLUB

GOOF

SLIP

TRIP



5 Character Answers:

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MISDO

STRAY



6 Character Answers:

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MESSUP



7 Character Answers:

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GOWRONG

STUMBLE



8 Character Answers:

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SLIPACOG



17 Character Answers:

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