Do Wrong, Right: Half the time they are fighting other villains it is for this reason.
City Guards: Some Arachnos mooks serve this role in the Rogue Isles, while the Arbiter Drones are invincible guardians of safe zones.
Charles Atlas Superpower: Arachnos Widows and Fortunatas.
Apart from being used to beat enemies, they can also fire blasts of energy or (in the case of Bane Spiders) poison opponents with their spikes or blades.
Carry a Big Stick: Arachnos soldiers primarily make use of powered maces for hand-to-hand combat.
Needless to say, they edit out any dissenting thoughts against Lord Recluse while they are at it. With all the psychic, mind-control and possession powers out there, Arachnos keeps itself from being compromised by making psychic-conditioning requisite to receive a promotion into the upper ranks.
Brainwashing for the Greater Good: One of the very, very few Card-Carrying Villain examples.
CITY OF HEROES LORE PARAGON PROTECTORS FREE
Better Living Through Evil: According to NPC chatter, a few Arbiter and Operative quest givers, Arachnos covers medical expenses, pays well, comes with company housing, free schooling for the children of soldiers, a generous retirement plan, sick days and even three weeks of paid vacation a year! There is a reason Arachnos never needs to draft anyone or use propaganda.
Bad Ass Normal: Most of the rank-and-file soldiers are regular humans just with really good military training and support, yet they can still take out entire teams of super-heroes, NPC or PC, if their opponents underestimate them.
This is also a base function of the Arachnos Arbiters, but for societal issues instead of combat.
Awesome by Analysis: Captains and Widows project stat boosts to all local soldiers, in-game this is due to Lord Recluse observing the situation through a Psychic Link and giving step-by-step instruction on what movements to anticipate, making soldiers react according to a super genius, so fast that its all basically intuitive.
Animal Motifs: As the name suggests, Arachnos has a spider theme - the only members that don't are the Mu Mystics.
Arachnos rules the Rogue Isles utterly, and constantly send forces to attack Paragon City. Villain Players work with/for Arachnos, while Heroes must defeat it at every turn. The biggest villain group of the setting, and one found through all level ranges.