Kural - 494

The foes who thought to triumph, find their thoughts were vain,
If hosts advance, seize vantage ground, and thence the fight maintain

Explanation
If they who draw near (to fight) choose a suitable place to approach (their enemy), the latter, will have to relinquish the thought which they once entertained, of conquering them.

Tamil Transliteration
Enniyaar Ennam Izhappar Itanarindhu
Thunniyaar Thunnich Cheyin.