Innate Combat Focus (3.5e Feat)
From D&D Wiki
 Innate Combat Focus [Combat Form]
You can focus your mind on battle in any situation.
Benefit: You can activate your combat focus as a standard action, by passing a Concentration check with a DC of 20. This allows you to enter a focused state several times per encounter, and even out of combat.
Normal: You can only gain Combat Focus once per encounter, and only after your first successful attack.
Special: A fighter may select this as one of his fighter bonus feats.