From the mechanical standpoint, the +2 Str is a nice thing to have when you want to give your max Str Barbarian character every bit of damage output you can. The roleplay hooks are less obvious, but still viable for those who wish to explore those elements.
- You get to play a race normally associated as being Evil, Savage, Brutal, and Violent. Some people actually just enjoy playing in that general direction.
- The other PC race usually looked at for those wanting to play evil is (or at least was at one point) Drow. With a half orc, you do not get the wangsty Emo / Goth stereotype you get from a Drow character.
- The Half Orc archetypes simply fit very, very well with certain character concepts. If you want a fighter who is simply more brutal and violent then other fighters, your not going to take a Halfling, Elf, Half-Elf, or Gnome (though going against type is often fun too).
- Under 4th Edition, if you want to be the strongest guy in the party, you either go with a Human (dropping the stat bonus on Str), a Dragonborn, a Goliath, or a Half Orc. If you want to have the sense of Honor, you probably go with a Dragonborn. If you want to be the 'Big guy', Golaith is a good fit. If you just want to be the really mean bastard, Half Orc is your best fit.
Basically, if I am going to make a melee fighter type, I prefer to go with either Dwarves or Half Orcs. If I want to be the one looking to do the most damage, I go with a Half Orc Barbarian. If I want to be the one that simply Will. Not. Die... I go with a Dwarf.
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