ADSR Sounds has released Bass Artillery, a collection of dubstep sounds for the Massive synthesizer instrument by Native Instruments.
Here are 50 NI massive presets made for dubstep or anything you can think of.
Inspired by artist such as Zomboy and Must Die! you to can create similar styles and add your take on the ‘Brostep’ genre.
The soundset is available for purchase for $20 USD.