This lumbering tortoise is the size of a pony and its head features a powerful, razor-sharp beak.
As a summoned, template, creature, this creature has several changes. Anything noted with  is what it gains from the template associated with the summoners’ alignment. Divine is always listed first, and Unholy afterwards.
Great Tortoise (CR 6)
N Large Divine / Unholy Magical Beast (Reptilian, [holy/shadow])
Init -2; Senses Darkvision 60 ft. [-/darkvision 120 ft. and see in darkness], low-light vision, scent; Perception +12
AC 23, touch 7, flat-footed 23 (-2 dex, +16 natural, -1 size)
hp 57  (6d10+24)
Fort +9, Ref +3, Will +2
Defensive Abilities [Dark Energy Resistance/Holy Energy Resistance]
Resist Earth 10, [holy 10/shadow 10]
Weakness Ice, [shadow/holy]
Speed 20 ft. [30 ft]
Melee Bite +13 (1d8+10 [+1d6 holy/shadow]))
Space 10 ft.; Reach 10 ft.
Special Attacks Breath Weapon (1d4+1 rounds, 30-ft. cone, DC 17, 4d6 water damage)
Str 24, Dex 6, Con 18, Int 2, Wis 10, Cha 6
Base Atk +6; CMB +13 (+15 vs. bull rush); CMD 21 (23 vs. bull rush; 25 vs. trip)
Feats Improved Bull Rush, Power Attack, Weapon Focus (bite)
Skills Acrobatics +9, Climb +17, Perception +12, Survival +10
As a move action, a great tortoise can completely withdraw into its shell, leaving him almost completely impervious to attack. When withdrawn he cannot move or attack as long as he remains in this state, a great tortoise gains a +8 bonus to his Armor Class and a +4 bonus on Reflex saves.
Divine – Dark Energy Resistance (Su)
When a divine creature is struck by an attack using shadow energy, energy drain, ability damage or drain, or hit point damage such as that from an inflict spell, the divine creature may make a level check (1d20 + total HD) against a DC equal to 11 + the attacking creature’s total Hit Dice. If the level check succeeds, the dark energy attack is canceled out in a bright flash. If the dark energy attack was dealt by a melee or melee touch attack, the creature that delivered it takes 2d6 points of holy damage.
Unholy – Holy Energy Resistance (Su)
When an unholy creature is struck by an attack using holy energy or cure spells, the unholy creature may make a level check (1d20 + total HD) against a DC equal to 11 + the attacking creature’s total Hit Dice. If the level check succeeds, the holy energy attack is canceled out in a bright flash. If the holy energy attack was dealt by a melee or melee touch attack, the creature that delivered it takes 2d6 points of shadow damage.