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Fury of the Grave (Ex): Once per day, a ch'ing shih can fly into a berserk fury. During this fury, the ch'ing shih temporarily gains a +8 bonus to Strength, a +2 morale bonus on Will saves, and the unholy toughness ability (which grants the ch'ing shih a bonus to its hit points equal to its Charisma modifier x its Hit Dice, but these hit points go away at the end of the fury. (These extra hit points are not lost first the way temporary hit points are.) While in a fury, a ch'ing shih cannot use any Charisma-, Dexterity-, or Intelligence-based skills (except for Balance, Escape Artist, Intimidate, and Ride), the Concentration skill, or any abilities that require patience or concentration, nor can it cast spells or activate magic items that require a command word, a spell trigger (such as a wand), or spell completion (such as a scroll) to function. It can use any feat he has except Combat Expertise, item creation feats, and metamagic feats. A fury lasts for a number of rounds equal to 3 + the ch'ing shih's Charisma modifier. A ch'ing shih may prematurely end its rage. At the end of the rage, the ch'ing shih loses the rage modifiers and restrictions. Entering a fury takes no time itself, but a ch'ing shih can do it only during its action, not in response to someone else's action.