Related Clues:

• Soft as it sounds, it is poisonous
• Footless for the summer, it seems
• Want to get so footless with ire
• The total this gives one is not even one foot long
• The cockney lacks the means to make it irate
• Poisonous mixture of 18 down
• The creeper will get to grips with this after a century and a half
• Soft like that it may be fatal
• Long to be the one that makes more of it, perhaps
• Poisonous to make some sound
• Might one do a long tot?
• Just as soft as it sounds, but far more dangerous
• The sort of poisonous ire one must aim for
• Perhaps summer might give the 10 across with poison
• Just as soft-sounding as it is dangerous