This gray armored lengthy, segmented horror writhes and twists, pulsing its venomous mandibles in search of prey.
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.
Hundlegs (CR 2)
AC 17, touch 13, flat-footed 14 (+3 dex, +4 natural)
hp 22  (3d8+9)
Fort +5, Ref +4, Will +2
Immune mind-affecting effects;
Resist earth 5 [holy 5/shadow 5]
Weakness Ice [shadow/holy]
Speed 40 ft. [50 ft], Climb 40 ft. [50 ft]
Melee Bite +5 (1d6+1 [+1d4 holy/shadow] plus poison), Sting +5 (1d6+1 plus poison)
Special Attacks Critical Attack
Str 12, Dex 16, Con 14, Int -, Wis 10, Cha 2
Base Atk +2; CMB +3; CMD 16 (can’t be tripped)
Feats Toughness, Weapon Finesse
Skills Climb +14, Perception +6, Stealth +13; Racial Modifiers +4 Perception, +8 Stealth
Critical Attack (Ex)
Once every 1d4 rounds as a standard action, the hundlegs can inflict more pain than normal. If they succeed at hitting with their bite attack, the damage is 1d6+1 x 1.5 for total damage.
Bite or sting — injury; save Fort DC 15; frequency 1/round for 6 rounds; effect 1d4 non-elemental damage; cure 1 save. The save DC is Constitution-based and includes a +2 racial bonus.