Was $44.95, now free. Expansion requires base game on PS4. Still full price for Xbox One players.
Expansion (by default) is already part of all digital copies of Rock Band 4, which is now $59.99 (was $90.95).
Expansion includes 44 new songs from Indie bands, as well as online multiplayer and a new mockumentary-styled campaign.
Way back when, I actually paid for this. Well, I rebought the game when it relaunched with the Rivals DLC thing in box.
I can't post it because the web store is EOL, but if you still have a PS3 and jam out to Rock Band in 2022, jump on and buy the Dr Feelgood album. I was feeling a Motley kick when the movie came out a couple years back and bought a song or two before finding the entire album, for whatever reason, was $8.55 normal price. All songs import into RB4.