The Bat Cave is of course the base of Batman and Robin. It serves as a place where you buy updates, bonuses and pick up missions. You reach it right after the first level, and further on you can choose what area to play. In the Bat Cave you will also find the Batman Collections which you will discover block by block, literally. After you complete the Story Mode, you unlock the Free Play.
In Free Mode you can pick additional secondary characters except Batman and Robin. Every Lego fellow you meet, good or bad, you

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can play it – this passively increase the playable characters to 40. You can even fight the Villains with your personal steward.
The not so obvious but important goal of every missions are those small Lego cubes. They give you Lego coins which is the main currency – you can buy new characters and bonuses with it. Often, you will find strange objects to help you progress by constructing various machines. Every mission has a fixed amount of cubes you have to find to achieve the Super Hero or Super Villain title.
You can call friends to help you control the second character while driving the Batmobile, but you will have to be on the same PC. Unfortunately, the multilayer was lost somewhere in the development papers.
Good or Bad?
Lego Batman, and also the previous games, offer a very high coefficient of replaying, especially if you want to collect all the MiniKit pieces and reveal the last of the secrets. Have in mind that only some characters can reach particular places or solve certain puzzles which you find in the Free Play mode.
You get access to the Arkam Sanitarium, and you can play from the villain's point of view. However, the authors didn't just change a few textures, you play the missions through their eyes – new puzzles, new plot and so on. This makes the game much more interesting and increases the playable levels up to 30 – and to play the extra stuff, you really need at least 20 hours.