Strength

Strength (represented by the icon in-game) is the attribute that grants health and health regeneration. For each point of strength a hero has, their maximum hit points increases by 19, and their health regeneration increases by 0.03 HP per second.

Strength heroes gain attack damage based upon their strength.

Strength Heroes
Strength heroes tend to have more health and thus tend to be able to take more damage than other heroes. Because of this, they often fit into initiator and tank roles. In addition, heroes with a large amount of strength may greatly increase the damage needed to bring a team down.

Strength heroes are almost all melee heroes, with the exception of Huskar, Wisp, and Dragon Knight when using Elder Dragon Form. (Phoenix is also a ranged strength hero, but has not yet been implemented into 'Dota 2.) At the moment, there are Strength Heroes implemented in Defense of the Ancients, and  implemented in Dota 2.

Below is a table of all heroes with strength as their primary attribute.