How to render grease pencil animations

Ive done a basic walkcycle in Blender using the new grease pencil animation feature but i have no idea how to properly render it.

I saw someone doing it using opengl but since its for a game and i need it in 300 * 300 images the whole thing look messed up ( lines way to big and distorted ).

Another person said they did it using freestyle but i dont know how.

Please help me out!