Brake, ABS, VSC, Check Engine, Master, Hybrid System Warning Lights all on

Title says it all (I hope?)

I have a 2006 Prius with 151,000 miles; purchased it used from a dealership, but based on service history, it's been in the Seattle area all its life.

Today, I drove it for 3 mins and the brake (yellow indicator only), VSC, check engine, and master warning lights all came on while I was driving (I can't recall if the ABS light and Hybrid System Warnings also came on). I parked the car in a nearby lot right-away and turned on/off multiple times. The master warning, check engine, and Hybrid Warning system lights persisted. I really don't know much about cars, so decided it was safest to have the car towed to a Toyota dealership. So my car is parked outside the dealership, pending service appointment in 2 days.

When I turned the car on outside the service center (after 30 mile / 50 minute tow), the red brake, ABS, VSC, check engine, master warning and hybrid system warning lights all came on. Turned off/on multiple times. Tried the IG-ON mode multiple times. All the warning lights persisted.

When I drove it around the parking lot, the only driving/maneuvering difference I noticed was the power steering seemed less powerful (i.e. I had to work harder to turn the car). But it was very manageable; just not as light as it usually is. Everything else, such as acceleration, braking, etc. seemed fine.

Background info: I parked the Prius from July - Oct 2014, jump started and drove it for two weeks, then parked in again Oct 2014 - Sep 2015, jump started multiple times and drove it for two weeks, and then parked it again Oct 2015 - Nov 2016 (because I was away during these times). During the extended parking, I did not hook it up with a battery charger (which I should have done). I also know the 12V battery has not been replaced since the car came off the line, thanks to the previous owner who maintained great service records.

Any guesses if my Prius is just loooong overdue for a 12V battery change or if there is a more significant issue?