It no work boss
$ java -jar Bullet_Strain.jar
Exception in thread "main" java.lang.UnsupportedClassVersionError: engine/Main : Unsupported major.minor version 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:482)

$ java -version
java version "1.7.0_91"
OpenJDK Runtime Environment (IcedTea 2.6.3) (Arch Linux build 7.u91_2.6.3-1-x86_64)
OpenJDK 64-Bit Server VM (build 24.91-b01, mixed mode)

absolutely *tremendous* sound effects. I was pleasantly surprised by how meaty everything sounded. It really leant a lot of weight to the combat, which was also quite well done with a nice amount of enemy variety.

I can't edit my comment, so have a second one:

my first problem was just that I wasn't using java 8 and Java doesn't happen to have a very good error message for that case

* I never got tumbling to work, for me pressing space did nothing, and I only accidentally rolled once when I clicked away from the window
* larger bullets seem to have janky hitboxes: I never quite got to screenshot-sized bullets because it became too easy to miss with only slightly bigger ones

+ The shooting does have a good sense of weight to it: even without upgrades I felt like I was wielding a scary thing that just annihilates trees (because it does)
- I didn't like the "ancient" back-pack thing: it was too big to get around without rolling (which I didn't have) and even if I could roll around it, it would discourage exploration and taking risks in fights because an enemy might spawn near it.

This is pretty fun, but rolling around everywhere gets annoying

@Alloyed: That's weird as heck about the tumbling (which I imagine is kind of annoying as Fervir said, even if you did get it working...). That said, monsters only ever spawn at the absolute edge of the map.

I suppose a faster move speed would have been better than (or in addition to) tumbling.

Oh. Tumble is shift, not spacebar. Sorry!