Scarlet Trooper

Scarlet Troopers are level 58-59 non-elite human paladins that spawn and escort.

When a player accepts the quest, she and eight Scarlet Troopers will spawn in Tyr's Hand. They follow a fixed path through Corin's Crossing, still walking on the path, to the Plaguewoods, and finally to Stratholme where they will despawn. Scarlet Troopers are not to be taken lightly and are in fact some of the tougher non-elites in the game. Demetria will rez them if they are killed before her, so don't bother with them until Demtria is dead. The Troopers along with Demetria will attack all undead or hostile enemies they encounter, including player characters.

Abilities

 * Hammer of Justice: Stuns the target for X amount of time. Can be dispelled. Does not stack. Believe to be on a ten second cooldown.
 * Divine Shield: Makes the caster invulnerable to all forms of damage and reduces attack speed by 50% for four (or six, I forgot) seconds. Cannot be (normally) dispelled.
 * Holy Light: Heals target for X amount of health. Causes Forbearance.

For information on strategy, see Demetria's article.

Additional Info
It is very possible that while encountering Demetria you will also encounter the Crimson Courier, who has her own entourage of elite warriors who frequently Intercept. There is no scripted event between the two, but the two will help each other. If the Courier and her entourage are added to the fight, it may cause a wipe.

She and her guards will attack Scourge they come across, especially when travelling through Corin's Crossing and Plaguewood. It is possible, if she and her platoon are engaged in multiple mobs, too pull her away, and whittler her down while her guards deal with the Scourge. Note, that once the guards take out the undead, they'll be on you within seconds, so kill Demetria quick. Even if she is dead, the guards will still probably engage you, but will be much easier to deal with now that Demtria is no longer around to rez them.