Natural Spikes

Type of Feat: Racial
Natural Spikes (Ex): A spiker's skin is replete with sharp, jagged spikes. A spiker can deal extra piercing damage on a successful grapple check, or deal piercing damage with a melee attack, as if she wore armor spikes. Because of their spiked skin, spikers have a difficult time wearing armor. The maximum Dexterity bonus of the armor is reduced by 1, and the armor check penalty is worsened by 2. For instance, a chain shirt worn by a spiker has a maximum Dexterity bonus of +3 (instead of +4) and an armor check penalty of -4 (rather than -2). These changes don't affect the armor's arcane spell failure chance, nor do they apply to shields used by the spiker.
Damage reduction 2/slashing or piercing: A spiker's spiny skin grants resistance to bludgeoning attacks, though piercing or slashing attacks slip through normally.