Pureblade

If a pureblade deals damage to an aberration, as an immediate action he can apply his studied target bonus against that target even if he didn't sneak attack it. In addition, a pureblade can attempt Knowledge (dungeoneering) skill checks untrained when trying to identify aberrations. This ability replaces track.

At 2nd level, as a standard action a pureblade can detect aberrations. This works like detect undead, except it detects aberrations instead of undead. This ability replaces the slayer talent received at 2nd level.

At 7th level, a pureblade becomes an expert at locating an aberration's weak points. The pureblade rolls twice to confirm critical hits against aberrations and keeps the higher roll. This ability replaces stalker.

At 8th level, a pureblade gains a +2 resistance bonus on saving throws against mind-affecting spells and effects. This bonus increases to +4 at 12th level and +6 at 16th level. In addition, once per day as a standard action, a pureblade can shed a magical effect placed on him by an aberration as break enchantment, using his slayer level as his caster level. A pureblade can use this ability twice per day at 12th level and three times per day at 16th level. This ability replaces the slayer talent received at 8th level.

At 20th level, a pureblade can use his master slayer ability on any aberration, even if it's not his studied target. This ability alters master slayer.