Related Clues:

• Invasion or hostile attack
• Sudden attack
• Bit of headway
• Invasion
• Hostile incursion
• New venture
• Hostile raid, or the route taken to get there
• Sudden incursion
• Inroad
• Sudden strike
• First attempt
• Damaging encroachment
• Tactical advancement
• Sortie
• Advance made at the expense of another