A ronin samurai gains the following abilities as he increases in level.
Self Reliant At 2nd level, the ronin learns to rely solely on himself, even in the most difficult of times. Whenever the ronin fails a Will saving throw against an effect with a duration greater than 1 round, he can attempt another saving throw at the end of the second round of the effect. If he makes this saving throw, it has the same effect as if he had made the original save (negating part or all of the effect). In addition, whenever a ronin is brought below 0 hit points, on his next turn he can roll twice to stabilize, taking the better result.
Without Master (Ex): At 8th level, the ronin's fierce independence allows him to overcome staggering odds. The ronin can summon up this willpower as an immediate action, and can use it in one of three ways. He can use his willpower whenever an attack would reduce him to fewer than 0 hit points but wouldn't kill him, to instead be at 1 hit point and conscious. He can use his willpower after making an attack roll to confirm a critical hit in order to reroll the confirmation roll. Finally, he can use his willpower to take 10 on a skill check during combat, even if the situation or the skill would not normally allow him to take 10. A ronin can use this ability once during a combat.
Chosen Destiny (Ex): At 15th level, the ronin is the master of his own destiny. Whenever the ronin makes a saving throw against a charm or compulsion effect, he may roll twice and take the better result. In addition, once per day, the ronin can treat any one d20 roll as if the result were a natural 20. He must declare the use of this ability before the roll is made.