>>5895381The Starter Pack by itself gives you access to all fifteen levels of the Story Mode, three franchise-focused Adventure Worlds (The LEGO Movie, LOTR, and DC), and a bonus area where you can beat up mooks forever.
There's a lot of unlockables that require abilities and characters that are sold separately, but you can essentially finish the game with just Wyldstyle, Gandalf, and Batman. Accomplishing 100% requires purchases, but you don't need every pack to do it.
The amount of stuff you get in the level packs varies, but it's always one full level, however long that level may be. Since none of the franchises in the Level Packs come in the Starter Pack, you also gain access to their respective Adventure Worlds, and I believe most of the minifigs in the Level Packs have exclusive abilities (e.g. Chell's Portal Gun, the Doctor's TARDIS, Ghost Traps).
