Old School (roughly everything before 2e) from the Swords and Wizardry Monster Book
Blink dogs are pack hunters, intelligent and usually friendly to those who are not of evil intent. They can teleport short distances (without error) and attack in the same turn – in most cases (75%) a blink dog will be able to teleport behind an opponent and attack from the rear (with appropriate bonuses).
Blink Dog: HD 4; AC 5; Atk 1 bite (1d6); Move 12; Save 13; CL/XP 4/120; Special: Teleport.
From the 3.5 SRD same monster trimmed slightly for brevity
Blink Dog click to see monster
Size/Type: Medium Magical Beast
Hit Dice: 4d10 (22 hp)
Speed: 40 ft. (8 squares)
Armor Class: 16 (+3 Dex, +3 natural), touch 13, flat-footed 13
Base Attack/Grapple: +4/+4
Attack: Bite +4 melee (1d6)
Full Attack: Bite +4 melee (1d6)
Space/Reach: 5 ft./5 ft.
Special Attacks: —
Special Qualities: Blink, darkvision 60 ft., dimension door, low-light vision, scent
Saves: Fort +4, Ref +7, Will +4
Abilities: Str 10, Dex 17, Con 10, Int 10, Wis 13, Cha 11
Skills: Hide +3, Listen +5, Sense Motive +3, Spot +5, Survival +4
Feats: Iron Will, Run, TrackB
Alignment: Usually lawful good
The blink dog is an intelligent canine that has a limited teleportation ability.
Blink dogs have their own language, a mixture of barks, yaps, whines, and growls that can transmit complex information.
Blink dogs hunt in packs, teleporting in a seemingly random fashion until they surround their prey, allowing some of them to take advantage of flanking.
A blink dog can use blink as the spell (caster level 8th), and can evoke or end the effect as a free action.
Dimension Door (Su)
A blink dog can teleport, as dimension door (caster level 8th), once per round as a free action. The ability affects only the blink dog, which never appears within a solid object and can act immediately after teleporting.
Smaller stat blocks mean more space for creativity and shorter prep time.