Possible Clues:

• Virulence
• Toxic substance
• Poisonous liquid of snakes
• Very little cash turning up, but yen is lost for acrimony
• The Po is on the move around the North
• What many a fang ejects
• Snake spit
• Money raised: a little bit at the end stolen out of spite
• Dangerous snake's weapon
• Virulent feeling against cash being raised finally going