[12:58:14] [Server thread/ERROR]: Could not load 'plugins\CombatTag.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.NoClassDefFoundError: net/minecraft/server/v1_7_R3/World
	at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:133) ~[spigot.jar:git-Spigot-01156a9]
	at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:336) ~[spigot.jar:git-Spigot-01156a9]
	at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:258) [spigot.jar:git-Spigot-01156a9]
	at org.bukkit.craftbukkit.v1_8_R1.CraftServer.loadPlugins(CraftServer.java:288) [spigot.jar:git-Spigot-01156a9]
	at net.minecraft.server.v1_8_R1.DedicatedServer.init(DedicatedServer.java:152) [spigot.jar:git-Spigot-01156a9]
	at net.minecraft.server.v1_8_R1.MinecraftServer.run(MinecraftServer.java:496) [spigot.jar:git-Spigot-01156a9]
	at java.lang.Thread.run(Unknown Source) [?:1.8.0_25]
Caused by: java.lang.NoClassDefFoundError: net/minecraft/server/v1_7_R3/World
	at java.lang.Class.forName0(Native Method) ~[?:1.8.0_25]
	at java.lang.Class.forName(Unknown Source) ~[?:1.8.0_25]
	at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:64) ~[spigot.jar:git-Spigot-01156a9]
	at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:129) ~[spigot.jar:git-Spigot-01156a9]
	... 6 more
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_7_R3.World
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:91) ~[spigot.jar:git-Spigot-01156a9]
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:86) ~[spigot.jar:git-Spigot-01156a9]
	at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_25]
	at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_25]
	at java.lang.Class.forName0(Native Method) ~[?:1.8.0_25]
	at java.lang.Class.forName(Unknown Source) ~[?:1.8.0_25]
	at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:64) ~[spigot.jar:git-Spigot-01156a9]
	at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:129) ~[spigot.jar:git-Spigot-01156a9]
	... 6 more