An issue that only occurs when trying to run pokecubes mod with sponge. Not sure whose side the issue is on, but figured id post it here first. Basically you cannot open the PC and it spams this each time you click it.

[00:22:28] [Server thread/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.lang.NullPointerException
at java.util.concurrent.FutureTask.report(Unknown Source) ~[?:1.8.0_92]
at java.util.concurrent.FutureTask.get(Unknown Source) ~[?:1.8.0_92]
at net.minecraft.util.Util.func_181617_a(SourceFile:46) [h.class:?]
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:666) [MinecraftServer.class:?]
at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:385) [lb.class:?]
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:611) [MinecraftServer.class:?]
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:469) [MinecraftServer.class:?]
at java.lang.Thread.run(Unknown Source) [?:1.8.0_92]
Caused by: java.lang.NullPointerException
at pokecube.core.CommonProxyPokecube.getPlayer(CommonProxyPokecube.java:73) ~[CommonProxyPokecube.class:?]
at pokecube.core.blocks.pc.InventoryPC.getPC(InventoryPC.java:122) ~[InventoryPC.class:?]
at pokecube.core.blocks.pc.BlockPC.func_180639_a(BlockPC.java:123) ~[BlockPC.class:?]
at net.minecraft.server.management.PlayerInteractionManager.func_187251_a(PlayerInteractionManager.java:179) ~[lt.class:?]
at net.minecraft.network.NetHandlerPlayServer.func_184337_a(NetHandlerPlayServer.java:680) ~[mc.class:?]
at net.minecraft.network.play.client.CPacketPlayerTryUseItemOnBlock.func_148833_a(SourceFile:55) ~[jh.class:?]
at net.minecraft.network.play.client.CPacketPlayerTryUseItemOnBlock.func_148833_a(SourceFile:11) ~[jh.class:?]
at org.spongepowered.common.network.PacketUtil.onProcessPacket(PacketUtil.java:121) ~[PacketUtil.class:1.9.4-1968-5.0.0-BETA-1503]
at net.minecraft.network.PacketThreadUtil$1.redirect$onProcessPacket$0(SourceFile:39) ~[fj$1.class:?]
at net.minecraft.network.PacketThreadUtil$1.run(SourceFile:13) ~[fj$1.class:?]
at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) ~[?:1.8.0_92]
at java.util.concurrent.FutureTask.run(Unknown Source) ~[?:1.8.0_92]
at net.minecraft.util.Util.func_181617_a(SourceFile:45) ~[h.class:?]
... 5 more

PokeCube Core: 3.3.8
PokeCube Mobs: 2.1.3
PokeCube Revival: 3.3.7
ThutCore: 3.1.5
Forge: 1976

seems fixed in newest builds of sponge and pokecubes