OK, I was somewhere in Arca Plant on the mission about you chasing your imposters. When I reached an area with a green laser, I walked towards it and accidentally got caught in the trap that immobilizes you(sorry, I forgot what it's called)(trap was in front of laser). Since the AI's are too stupid to save me, the laser got stuck in the trap too. lol. So after the the trap exploded, the laser vanished. There was then wavy red lines that causes you to be cast w slow(also don't know the name of it). So be careful not to get in this mess unless you already have.

P.S. the "disease" will stay even if you exit the area and re-enter.

After completing a few quests, Nicholas will tel you about the sewer. Go to the very bottom of the city and you will find a manhole. Go in and there will be special shops!

There are some access to some special rooms in the fields.
1. The Bakery, the bakery is only accessible in the Valley and Wetlands. (I forgot but when you go in, you might get a new quest)

2. Pizza Shop, this shop is only accessible in Arca Plant. There's a shop that allows you to buy Pizza Boxes, it is a armor, and has good stats if you grind them to the max. (Their max is +99, also one of the only ones that can be grinded to +99.)

I'm still trying to find if both of them can be accessible in multiplayer. so if it does message me!