Gungrave G.O.R.E (US)

Way easier than it seems at first. On the 3rd level you'll have some big areas with lots of guys, use your Demolition Shot in the middle of a big group for lots of Art Score, there is a point where you'll need to evade spinning rotating spikes, just after this puts you in a huge group smash a Demo shot for around 800 just there.

I was over 2.5k by the 50% mark of this level. Ever time you can use Demo shot on a big crowd, use it and build it again, using Fury and Executions also helps.