CR 4 or less monster thread!

[Khisanth the Ancient]

This thread has CR 4 or lss templated critters. I might also include one more powerful, though.
Plaguebringer (Rat, Monster of Legend)
Tiny Outsider
Hit Dice: 1/4d8+5 (6hp)
Initiative: +9 (+5 Dex, +4 Improved Initiative)
Speed: 15 ft., climb 15ft.
AC: 22 (+2 size,+5 Dex, +5 natural), touch 17, flat-footed 17
Attacks: Bite +4 (+1 Base, +1 Str, +2 size)
Damage: Bite 1d4+1
Face/Reach: 2-1/2 ft./0 ft.
Special Attacks: Raging blood
Special Qualities: Immunities, greater damage
Saves: Fort +7, Ref +7, Will +4
Abilities: Str 12, Dex 21, Con 20, Int 4, Wis 14, Cha 10
Skills: Balance +10, Climb +12, Hide +18, Move Silently +10
Feats: Weapon Finesse, Improved Initiative (B), Multiattack (B)
Climate/Terrain: Any land and underground
Organization: Swarm (10-100)
Challenge Rating: 2
Treasure: None
Alignment: Always neutral
Advancement: -
A plaguebringer is a powerful version of a rat, often granted its powers by a deity of thievery and stealth (such as Olidammara), disease, or poisons. Though only slightly larger than their normal kin, they are far more powerful. A single plaguebringer may lead a swarm of normal rats. Its name comes from its virulent blood, which some believe to be poisonous or diseased – it is actually a potent acid.
COMBAT
A plaguebringer attacks its foes viciously. It uses its greater damage power to full effect.
Raging Blood (Su): Each time damage is dealt to a plaguebringer with a slashing or piercing damage, its blood sprays outward in a 5-foot cone, dealing 1d4 points of acid damage to all within range (no saving throw). A plaguebringer is not harmed by its own blood.
Immunities (Ex): A plaguebringer is immune to polymorphing and acid.
Greater Damage (Ex): A plaguebringer’s bite deals 1d4 points of base damage, not 1d3.

 

[Khisanth the Ancient]

Myrnicol the Burnt (Fiendish Lizard)
Tiny Magical Beast
Hit Dice: 1/2d8 (2 hp)
Initiative: +2 (Dex)
Speed: 20 ft., climb 20 ft.
AC: 14 (+2 size, +2 Dex)
Attacks: Bite +4 melee
Damage: Bite 1d4 - 4
Face/Reach: 2 1/2 ft. by 2 1/2 ft. / 0 ft.
Special Attacks: Smite good
Special Qualities: Darkvision 60 ft., SR 1, cold resistance 5, fire resistance 5
Saves: Fort +2, Ref +4, Will +1
Abilities: Str 3, Dex 15, Con 10, Int 3, Wis 12, Cha 2
Skills: Balance +10, Climb +12, Hide +13, Listen +4, Spot +4
Feats: Weapon Finesse (bite)
Climate/Terrain: Any land and underground
Organization: Solitary
CR: 1/6
Treasure: None
Alignment: Neutral evil
Advancement: -

At one time, there were many lizards in one small village. But, over a period of three months, they disappeared. Unknown to the villagers, the reason behind this disappearance was Myrnicol the Burnt.
Myrnicol resembles a common lizard outwardly, save that he is slightly larger - but not outside the range of natural variation. However, this somewhat unassuming body conceals the spirit of a demon.
He devoured the other lizards, and is now looking for bigger prey...
COMBAT
Myrnicol smites good in the first round if facing good creatures.
Smite Good (Su): Once per day, Myrnicol may make a normal attack to deal 1 extra point of damage to a good foe.