java.lang.IllegalAccessError: tried to access field net.minecraft.entity.projectile.EntityArrow.field_70255_ao from class mixac1.dangerrpg.entity.projectile.core.EntityProjectile
at mixac1.dangerrpg.entity.projectile.core.EntityProjectile.<init>(EntityProjectile.java:30)
at mixac1.dangerrpg.entity.projectile.core.EntityProjectile.<init>(EntityProjectile.java:48)
at mixac1.dangerrpg.entity.projectile.core.EntityWithStack.<init>(EntityWithStack.java:29)
at mixac1.dangerrpg.entity.projectile.core.EntityCommonMagic.<init>(EntityCommonMagic.java:33)
at mixac1.dangerrpg.entity.projectile.EntityMagicOrb.<init>(EntityMagicOrb.java:28)
at mixac1.dangerrpg.entity.projectile.EntityPowerMagicOrb.<init>(EntityPowerMagicOrb.java:28)
at mixac1.dangerrpg.item.weapon.ItemPowerStaff.getEntityMagicOrb(ItemPowerStaff.java:19)
at mixac1.dangerrpg.item.weapon.ItemRPGStaff.func_77615_a(ItemRPGStaff.java:82)
at net.minecraft.item.ItemStack.func_77974_b(ItemStack.java:402)
at net.minecraft.entity.player.EntityPlayer.func_71034_by(EntityPlayer.java:196)
at net.minecraft.network.NetHandlerPlayServer.func_147345_a(NetHandlerPlayServer.java:439)
at net.minecraft.network.play.client.C07PacketPlayerDigging.func_148833_a(SourceFile:53)
at net.minecraft.network.play.client.C07PacketPlayerDigging.func_148833_a(SourceFile:8)
at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212)
at net.minecraft.network.NetworkSystem.func_151269_c(NetworkSystem.java:165)
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:659)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:547)
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:111)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:427)
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685)
Crash :