[16:05:47] [Server thread/ERROR]: Could not load 'plugins/MRCasino-1.0-SNAPSHOT.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.UnsupportedClassVersionError: me/sturm/mrcasino/MrCasinoPlugin has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0
	at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:131) ~[core.jar:git-Paper-33d42c8e]
	at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:329) ~[core.jar:git-Paper-33d42c8e]
	at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:251) ~[core.jar:git-Paper-33d42c8e]
	at org.bukkit.craftbukkit.v1_12_R1.CraftServer.loadPlugins(CraftServer.java:318) ~[core.jar:git-Paper-33d42c8e]
	at net.minecraft.server.v1_12_R1.DedicatedServer.init(DedicatedServer.java:222) ~[core.jar:git-Paper-33d42c8e]
	at net.minecraft.server.v1_12_R1.MinecraftServer.run(MinecraftServer.java:616) ~[core.jar:git-Paper-33d42c8e]
	at java.lang.Thread.run(Thread.java:750) [?:1.8.0_332]
Caused by: java.lang.UnsupportedClassVersionError: me/sturm/mrcasino/MrCasinoPlugin has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0
	at java.lang.ClassLoader.defineClass1(Native Method) ~[?:1.8.0_332]
	at java.lang.ClassLoader.defineClass(ClassLoader.java:756) ~[?:1.8.0_332]
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) ~[?:1.8.0_332]
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:152) ~[core.jar:git-Paper-33d42c8e]
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:104) ~[core.jar:git-Paper-33d42c8e]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:418) ~[?:1.8.0_332]
	at java.lang.ClassLoader.loadClass(ClassLoader.java:351) ~[?:1.8.0_332]
	at java.lang.Class.forName0(Native Method) ~[?:1.8.0_332]
	at java.lang.Class.forName(Class.java:348) ~[?:1.8.0_332]
	at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:82) ~[core.jar:git-Paper-33d42c8e]
	at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:127) ~[core.jar:git-Paper-33d42c8e]
	... 6 more