Blood Horse (CR 3)

Large Magical Beast
Alignment: Always chaotic evil
Initiative: +4 (Dex); Senses: blindsight, darkvision 20 ft. detect good, Listen +11, and Spot +10

AC: 17 (-1 size, +4 Dex, +4 natural), touch 13, flat-footed 13
Hit Dice: 4d10+12 (34 hp)
Fort +7, Ref +8, Will +2
Speed: 40 ft., fly 80 ft. (average)
Space: 10 ft./5 ft.
Base Attack +4; Grapple +3
Attack: Bite +7 melee, 2 claws +5 melee
Full Attack: Bite +7 melee, 2 claws +5 melee
Damage: Bite 1d8+4, claw 1d4+2
Special Attacks/Actions: Sonic screech, pounce, rake 1d4+2, blood drain
Abilities: Str 18, Dex 18, Con 17, Int 6, Wis 13, Cha 7
Special Qualities:
Feats: Multiattack
Skills: Listen +11, Move Silently +7, and Spot +10
Advancement: 5-8 (Large), 9-12 (Huge)
Climate/Terrain: Temperate and warm forest, hills, and plains.
Organization: Solitary, pair, herd (5-8)
Treasure/Possessions: None

Source: Dragon #299

Sonic Screech (Su): As a standard action. the blood horse can give a piercing screech once every 1d4 rounds. Creatures in a 20-foot radius take 1d4 points of sonic damage and must make Fortitude save (DC 15) to avoid being stunned for 1 round and deafened for 1d4 rounds. A stunned creature cannot act and loses any Dexterity bonus to AC. Opponents gain a +2 bonus to attack a stunned creature. A deafened character automatically fails Listen checks. suffers a -4 penalty on initiative, and has a 20% chance to miscast and lose any spell with a verbal component. Deafened creatures cannot be further stunned or deafened, but they suffer damage from a sonic screech normally. A silence spell negates this ability.

Blood Drain (Ex): A blood horse can suck blood from a living victim with its fangs. If it pins the foe during a grapple it delivers an automatic bite attack and drains blood, inflicting; 1d2 points of Constitution damage each round it maintains the pin.

Blindsight (Ex): Blood horses can "see" by emitting high-frequency sounds, inaudible to most other creatures, that let them locate objects and creatures within 20 feet. A Silence spell negates this ability and forces the blood horse to rely on its weak vision which, including its darkvision and low light vision, has a maximum range of 20 feet.

Detect Good (Sp): Blood horses can detect good at will, as the spell cast by a 1st-level cleric.

Skills: Blood horses receive a +4 racial bonus to Listen and Spot checks.

Blood horses usually soften up tough targets with their sonic screech and then pounce on their prey, diving from above, with teeth and claws bared. They generally prefer to drain blood only from foes who are incapable of defending themselves.