Skeleton, Gray Render* (CR 5)

Large Undead
Alignment: Always neutral evil
Initiative: +5 (+1 Dex, +4 Improved Initiative)

AC: 13 (-1 Size, +1 Dex, +3 natural), touch 13, flat-footed 12
Hit Dice: 10d12 (65 hp)
Fort +3, Ref +4, Will +7
Speed: 30 ft.
Space: 5 ft./5 ft.
Base Attack +5; Grapple +5
Attack: Bite +10 melee, 2 claws +5 melee (base +5 Str +6 Size)
Full Attack: Bite +10 melee, 2 claws +5 melee (base +5 Str +6 Size)
Damage: Bite 2d6+6, claw 1d6+3
Special Attacks/Actions: -
Abilities: Str 23, Dex 12, Con -, Int -, Wis 10, Cha 1
Special Qualities: Undead, skeleton immunities
Feats: Improved Initiative
Skills: -
Advancement: 11-15 HD (Large); 16-21 (Huge)
Climate/Terrain: Any land and underground
Organization: Any
Treasure/Possessions: None

Source: Web

Skeletons are the animated bones of the dead, mindless automatons that obey the orders of their evil masters.

A skeleton does only what it is ordered to do. It can draw no conclusions of its own and takes no initiative. Because of this limitation, its instructions must always be simple, such as "Kill anyone who enters this chamber."

A skeleton attacks until it is destroyed, for that is what it was created to do. The threat posed by a skeleton depends primarily on its size.