A basic bat in a cave.
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.
Bat, Cave (CR 1)
AC 14, touch 13; flat-footed 12 (+2 Dex, +1 size, +1 natural)
hp 13  (2d10+1)
Fort +2, Ref +5, Will +2
[Resist holy 5/shadow 5]
Speed 15 ft. [25 ft], Fly 40 ft. [50 ft] (good)
Melee Bite +5 (1d6-1 [+1 holy/shadow])
Space 5 ft.; Reach 5 ft.
Special Attacks Blood Drain, Critical Attack, Screech
Str 9, Dex 15, Con 8, Int 2, Wis 14, Cha 5
Base Atk +2; CMB +0; CMD 10
Feats Toughness*, Weapon Finesse
Skills Fly +13, Perception +6; Racial Modifiers Perception +4
Blood Drain (Su)
Once per day, a cave bat can drain the blood from a target within 30 feet. The target must make a Fortitude save (DC 13) or take 1d8 points of shadow damage and the cave bat is healed for that much. Blue mages may learn this ability as a 1st level spell (Knowledge: Arcana DC 17).
Critical Attack (Ex)
Once every 1d4 rounds as a standard action, the cave bat 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.
Once per day as a standard action, a cave bat can produce an ear-splitting screech that stuns non-bats in a 20-foot-radius burst. All creatures within the area must make a DC 10 Fortitude save or be staggered for 1d2 rounds. Other bats are immune to this effect. This is a sonic mind-affecting effect. The save DC is Constitution-based.