Many abilities require one or more components in order to be executed.
Verbal Components
If an ability has a verbal component, the creature executing it must be able to speak to do so. The must not be deaf.
Somatic Components
If an ability has a somatic component, the creature executing it must have at least one free hand to do so. If the creature has an arm hack then it must have both hands free. If the creature has two arm hacks then it cannot execute the ability.
Material Components
If an ability has a material component, the creature executing it must have the material component on hand to do so. The specific material component is listed in the ability's description. Material components are consumed by the ability unless otherwise noted.