You'll need 100 action figures spread around the map, when you get close they start glowing which is super handy in darker spots. The comic store area is a good starting point, grab an online map cause doing this blind is pretty rough. Taking screenshots while collecting helps track progress, and following a video guide split into sections makes it way less tedious.

Once you've got all 100, swing by the hardcore comic store for the outfit and some bonus rp, no need to wait for an email or anything. Good to know some older guides talk about a special shotgun but that's not part of this anymore, just the outfit and rp these days. Probably best to work through this in chunks instead of one massive collection run, since server disconnects can be annoying during longer sessions.

If you're feeling lost at first, start around the city center and work your way out, makes it easier to keep track. Most figures are pretty visible once you're close enough but some are tucked away in weird spots so keep an eye on your minimap.