NightFall hero question

What is the difference between heroes and henchemans?

Hero:

You can switch their skills, order them to use the skills you gave them.
You can give them any weps you want(not costumized for other characters though)
You can rune them up, so their builds become stronger.
You can make them travel to a part of your compass via the flag's that are around it.

Henchmen:
You can make them travel to a part of your compass via the flag's that are around it.

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Heroes owns henchmen.

Ah I see... And how do I exactly buy skills for my heroes. I'm an elementalist, so what if i want to buy skills for my warrior... Where can I buy that?

Yes there is a HUGE difference between Henchman and Hero.

Hench have defined builds and equips and lvl, heroes you can customize skills and 2nd profession, give whatever rune/insignia you want and weapons, you can read more in the links I posted.

Heroes uses skills which are unlocked for your account. See more: http://wiki.guildwars.com/wiki/Skills

There's two really easy ways of getting skills for heroes.
#1 You create and play a character with the primary profession you want to unlock skills for, and then you learn skills on that character as you would on your ele.
#2 You play PvP in order to unlock balthazar factions which in turn can be used to unlock skills at a priest of balthazar (pvp-only characters do also use unlocked skills).
#2,1 You farm zaishen elite with a pvp-only trapper with a trapper's build which you've gotten in one way or another together with 3 other players. It's one of the easiest farms in the game and very accessible.

There's many ways of getting skills for your hero warrior, but the one I've used most is through this guy: http://wiki.guildwars.com/wiki/Priest_of_Balthazar It takes some pvping or zaishen elite farming though.

It's not just limited to primary profession, though. Once a character is "ascended" they can change their secondary profession to anything and as often as they want. If all you play is an elementalist, you can change your secondary to Warrior and buy skills from skill trainers for your warrior heroes. And then change to another secondary to buy skills for heroes of that profession.

It can get expensive this way, though. I often create temp characters of every profession in either Factions or Nightfall to grab up free training skills and buy skills from the starting skill trainers for cheap. This gives my heroes some skills to get along with until I have enough bank and access to later areas to grab the good ones I may want.

You can also use Hero Skill Trainers, which too will unlock the skill for your account. There's one in every major town in Nightfall, and in the odd outpost too.