Older Beholder
Hero
Just a quick idea on adding Warforged to a campaign...
Have the players go on an adventure back a few hundred years in time and stop the assassination of a tinker gnome (or cleric of Gond, or whatever). If successful it turns out the tinker goes on to invent the first Warforged, and when the characters return to the present day they find the construct race filling out the ranks of the nation's army.
So, when it next comes time to make up a character in a new campaign using the same setting, Warforged are now an option and the players can feel some sense of accomplishment that it was their doing that made it possible.
Time travel/changing the past is a good way to add, or remove anything you want from a campaign.
Have the players go on an adventure back a few hundred years in time and stop the assassination of a tinker gnome (or cleric of Gond, or whatever). If successful it turns out the tinker goes on to invent the first Warforged, and when the characters return to the present day they find the construct race filling out the ranks of the nation's army.
So, when it next comes time to make up a character in a new campaign using the same setting, Warforged are now an option and the players can feel some sense of accomplishment that it was their doing that made it possible.
Time travel/changing the past is a good way to add, or remove anything you want from a campaign.