Dexterity is a measure of hand-eye coordination, precision, and manual dexterity.
Your Dexterity rank applies to:
- Attack checks for ranged attacks.
- Sleight of Hand and Vehicles skill checks.
- Dexterity checks for feats of fine control and precision when a specific skill doesn’t apply.
A creature with no Dexterity cannot manipulate objects and hence cannot make physical attacks
Mutants & Masterminds Hero’s Handbook, Copyright 2011, Green Ronin Publishing; Author Steve Kenson. Chapter-3 Abilities, Pg 54-59
D20Hero SRD Ability Article- http://www.d20herosrd.com/3-abilities