The MBK Center is a little different than most of Bangkok malls, it features over 2000 Shops from proper authentic merchandise to cheap Asian copies. Once (in 1985) it was the largest mall in Asia, a bit aged in 2014, still through its diversity a it is still a frequent destination for locals.
The MBK Center offers a huge variety of different shops and restaurants, medium price ranged higher than one would expect, but you can still get some bargains here and find some interesting stuff if you keep exploring it. Like most of Bangkok malls it has a good cinema at the top of the shopping complex.
There is a good console game stop at the 6th floor to buy Playstation, Xbox or Nintendo games. Even the prices are not too cheap here either...