Goblin

At a glance:
Diminutive dwellers of deep, dark demesnes.

Speed: 30ft.
Size: Small
Ether: Flow.
Darkvision: Yes.

Special Features:
Tunnelsense. You can always tell whether or not you are alone in an enclosed space, even if you cannot otherwise perceive the creature that's there. This ability does not tell you what kind of creature is present, nor how many, only that there is at least one in the same area as you.
Ambusher. When you make a Hide check and no enemies are aware of you, add an additional +4 to the result.