Killing a Signiferi of the Hand results in the following faction changes:-
Your faction standing with Hand of Seru got worse. Your faction standing with Eye of Seru got better. Your faction standing with Heart of Seru got better. Your faction standing with Seru got worse. Your faction standing with Hand Legionnaires got worse. Your faction standing with Validus Custodus got better. Your faction standing with Magus Conlegium got better.
LEVEL RANGE: These guys level range is actually 64-67. they con blue->yellow at 65, and always red at 61.
don't let their level fool you though, these guys are gimps. they go down fast and hit for about 200 max. the tough part is splitting them as pacify doesn't work on the mobs > 65.
CLASS: They are paladins, even though many are seen dual weilding, but they do occasionally lay on hands which is rather annoying.
LOCATION: These mobs are found in the southwest-most building in Sanctus Seru on the top floor. go up the stairs and around until you see 2 hallways perpendicular to each other. there is one mob at the end of each, guarding a portal (click it) that leads to another floor (which i believe is where the prae boss mob spawns for 4th earring.. 1 in each building) containing about 8-10 more of these mobs.
If you are a rogue doing this quest, and are lvl 65, then you can pickpocket all mobs BUT this one for a chance of getting the scrolls, as they are NOT magic items, thus pickable. they are LORE and NODROP.