I like the melding of two different games. You collect your resources to help you with completing your ultimate goal of beating the old man. I also liked how you made the players weapon basically be an instant shot where the enemies had projectiles so you felt like this powerful gunslinger and the slight slowing of time when you make a hit was a nice effect. Also the way you represented the players bullets and the reload animation was really cool
I dunno if this is b/c I beat the old man but I got like 9 million coins haha so basically I could play him as many times as I wanted. I had a lot of fun playing.