Microlite 20 stats: HD 2d8+8 (17 hp), AC 15, Gate-touch +3 (2d12+3, phys+Str DC 14 for half)
Gatables are lanky blue humanoids with six beady eyes and no nose. Their origins are a mystery, and as a species they are very secretive, and very paranoid. They only ever fight in self defense, but their rampant paranoia means that they tend to interpret totally innocent things as a prelude to an attack. They usually retreat once either they or their opponent has taken damage, but often return to harass their enemies at a later date.
Gatables can pull open gates through the fabric of reality. Opening a gate to anywhere is a standard action. Once a Gatable has walked through the gate, it remains open until the Gatable's next turn, or until somebody else tries to jump through it. Somebody triying to jump through a gatable gate must succeed a DC 20 Phys + Dex check, or else end up flat on their face as the gate closed before he got there. Whether the character succeeded in passing through the gate or not, it then closes. Gatables can also use this power as an attack, pushing parts of a target through small gates to random places.
For Planescape buffs: no Gatable has ever been seen in Sigil. Some think that the race once worshipped Aoskar, god of portals, and thus fear the retribution of the Lady of Pain if they venture into the city, while most believe that the Gatables are just reluctant to travel anywhere their gating power won't allow them to escape from.