Related Clues:

• They get to the total of the last of 20 across
• Even without legs they may totter along
• They make an afterthought that's poisonous
• In addition they've got not one foot among them
• To a total extent they'll give one the coup de grace
• They're like a poisonous afterthought
• Pass the poison from them
• The like of poisonous second thoughts
• Serpentine summers?
• 'Like an afterthought, they may be the death of you (4)'
• They have 19 across like an afterthought
• Like to be poisonous at the end
• How do they seem to totter along without legs?
• Summer's creatures get footless
• What a poisonous afterthought like this