Kural - 492

Though skill in war combine with courage tried on battle-field,
The added gain of fort doth great advantage yield

Explanation
Even to those who are men of power and expedients, an attack in connection with a fortification will yield many advantages.

Tamil Transliteration
Muranserndha Moimpi Navarkkum Aranserndhaam
Aakkam Palavun Tharum.