One thing i feel this game seems to be missing for me is having the ability to 'challenge' your own score. It would be amazing if you could have a 'arena' as such where there are countless types of cover where you start of wave/round 1, the enemies would start of low level (basic troops) and as you progress they get stronger/bigger waves) and every 5/10 waves you get bonus encounters (bosses) where for every boss you beat you get a reward, however every say 20 waves you complete you get a chance at a exotic/special item (king of like vog has it's own gear). This would be such a brilliant challenge for myself as i love survival game types! Please leave your opinions!