Watch out, they bite.
The Arachnos Widow is an epic archetype for villains that can only be created after you have advanced one of the villains on your account to level 50. They begin with access to two power pools: Widow Training and Teamwork. Widow Training is a powerset that has a number of light, medium and heavy melee and medium ranged attacks that do lethal and venomous damage. Teamwork provides many self and group buffs that improve defenses, attack statistics and resistances, making Widows more desirable for groups. They aren’t penalized for soloing, which they can do quite well, although they don’t quite have the defensive fortitude of the Arachnos Soldier. Like that archetype, they start with limited costume selection but gain access to another costume slot once they reach level 10.
When the Widow reaches level 24, they can choose between two branching advancement paths: Night Widow and Fortunata. This gains them a new primary and secondary powerset and gives them very divergent playstyles. Night Widow is a continuation of the initial powerset, although with greater stealth capabilities. Like the Stalker, they can get critical damage for many of their attacks when they strike from hiding. This makes them phenemonal single target damagers with greater survivability relative to that normal archetype. The Night Window Training powerset has some strong psionic attacks along with some additional melee abilities. They also get Smoke Grenade, which reduces the perception of their targets greatly, helping them to get into stealth that much easier. They also get a secondary powerset, Widow Teamwork, which focuses on stealth and attack power buffs.
Fortunatas take a very different path, essentially transforming into an entirely different archetype. They use powerful psionic assaults to control the battlefield, with abilities like Subdue, a ranged immobilize, and Dominate, a single target hold. The pool also has a number of psionic ranged attacks like Telekenetic Blast, which has a knockback component, and Psychic Wail, and area of effect attack with a disorienting component. The Fortunata Teamwork secondary powerset contains a stealth ability along with some additional crowd control and group buffs. Confuse allows them to confuse a single target, while Aura of Confusion makes it so that all of the enemies around the Fortunata have a chance at becoming confused. Mind Link gives the group additional to-hit chance, defense and psionic resistance.
If you don’t like the choice that you’ve made after level 24, you can always respec and choose a new path.