This is with Vanilla MC launcher, not a twitch pack nor twitch launcher.

[11:25:32] [main/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.lang.IndexOutOfBoundsException
at java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[?:1.8.0_25]
at java.util.concurrent.FutureTask.get(FutureTask.java:192) ~[?:1.8.0_25]
at net.minecraft.util.Util.func_181617_a(SourceFile:47) [h.class:?]
at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:1086) [bib.class:?]
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:397) [bib.class:?]
at net.minecraft.client.main.Main.main(SourceFile:123) [Main.class:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_25]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_25]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_25]
at java.lang.reflect.Method.invoke(Method.java:483) ~[?:1.8.0_25]
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?]
at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
Caused by: java.lang.IndexOutOfBoundsException
at io.netty.buffer.EmptyByteBuf.readUnsignedByte(EmptyByteBuf.java:535) ~[netty-all-4.1.9.Final.jar:4.1.9.Final]
at codechicken.lib.packet.PacketCustom.readUnsignedByte(PacketCustom.java:722) ~[PacketCustom.class:?]
at codechicken.lib.packet.PacketCustom.(PacketCustom.java:219) ~[PacketCustom.class:?]
at codechicken.lib.packet.PacketCustom.fromNBTTag(PacketCustom.java:343) ~[PacketCustom.class:?]
at codechicken.enderstorage.tile.TileFrequencyOwner.handleUpdateTag(TileFrequencyOwner.java:102) ~[TileFrequencyOwner.class:?]
at net.minecraft.client.network.NetHandlerPlayClient.func_147263_a(NetHandlerPlayClient.java:760) ~[brz.class:?]
at net.minecraft.network.play.server.SPacketChunkData.func_148833_a(SourceFile:96) ~[je.class:?]
at net.minecraft.network.play.server.SPacketChunkData.func_148833_a(SourceFile:18) ~[je.class:?]
at net.minecraft.network.PacketThreadUtil$1.run(SourceFile:13) ~[hv$1.class:?]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) ~[?:1.8.0_25]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[?:1.8.0_25]
at net.minecraft.util.Util.func_181617_a(SourceFile:46) ~[h.class:?]
... 9 more
[11:25:32] [main/INFO]: [CHAT] Teleported to 'base'!
[11:26:18] [main/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.lang.NullPointerException
at java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[?:1.8.0_25]
at java.util.concurrent.FutureTask.get(FutureTask.java:192) ~[?:1.8.0_25]
at net.minecraft.util.Util.func_181617_a(SourceFile:47) [h.class:?]
at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:1086) [bib.class:?]
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:397) [bib.class:?]
at net.minecraft.client.main.Main.main(SourceFile:123) [Main.class:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_25]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_25]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_25]
at java.lang.reflect.Method.invoke(Method.java:483) ~[?:1.8.0_25]
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?]
at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
Caused by: java.lang.NullPointerException
at net.minecraft.client.network.NetHandlerPlayClient.func_147263_a(NetHandlerPlayClient.java:740) ~[brz.class:?]
at net.minecraft.network.play.server.SPacketChunkData.func_148833_a(SourceFile:96) ~[je.class:?]
at net.minecraft.network.play.server.SPacketChunkData.func_148833_a(SourceFile:18) ~[je.class:?]
at net.minecraft.network.PacketThreadUtil$1.run(SourceFile:13) ~[hv$1.class:?]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) ~[?:1.8.0_25]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[?:1.8.0_25]
at net.minecraft.util.Util.func_181617_a(SourceFile:46) ~[h.class:?]
... 9 more
[11:26:18] [main/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.lang.NullPointerException
at java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[?:1.8.0_25]
at java.util.concurrent.FutureTask.get(FutureTask.java:192) ~[?:1.8.0_25]
at net.minecraft.util.Util.func_181617_a(SourceFile:47) [h.class:?]
at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:1086) [bib.class:?]
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:397) [bib.class:?]
at net.minecraft.client.main.Main.main(SourceFile:123) [Main.class:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_25]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_25]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_25]
at java.lang.reflect.Method.invoke(Method.java:483) ~[?:1.8.0_25]
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?]
at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
Caused by: java.lang.NullPointerException
at net.minecraft.client.network.NetHandlerPlayClient.func_147263_a(NetHandlerPlayClient.java:740) ~[brz.class:?]
at net.minecraft.network.play.server.SPacketChunkData.func_148833_a(SourceFile:96) ~[je.class:?]
at net.minecraft.network.play.server.SPacketChunkData.func_148833_a(SourceFile:18) ~[je.class:?]
at net.minecraft.network.PacketThreadUtil$1.run(SourceFile:13) ~[hv$1.class:?]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) ~[?:1.8.0_25]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[?:1.8.0_25]
at net.minecraft.util.Util.func_181617_a(SourceFile:46) ~[h.class:?]
... 9 more
[11:26:18] [main/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.lang.NullPointerException
at java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[?:1.8.0_25]
at java.util.concurrent.FutureTask.get(FutureTask.java:192) ~[?:1.8.0_25]
at net.minecraft.util.Util.func_181617_a(SourceFile:47) [h.class:?]
at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:1086) [bib.class:?]
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:397) [bib.class:?]
at net.minecraft.client.main.Main.main(SourceFile:123) [Main.class:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_25]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_25]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_25]
at java.lang.reflect.Method.invoke(Method.java:483) ~[?:1.8.0_25]
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?]
at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
Caused by: java.lang.NullPointerException
at net.minecraft.client.network.NetHandlerPlayClient.func_147263_a(NetHandlerPlayClient.java:740) ~[brz.class:?]
at net.minecraft.network.play.server.SPacketChunkData.func_148833_a(SourceFile:96) ~[je.class:?]
at net.minecraft.network.play.server.SPacketChunkData.func_148833_a(SourceFile:18) ~[je.class:?]
at net.minecraft.network.PacketThreadUtil$1.run(SourceFile:13) ~[hv$1.class:?]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) ~[?:1.8.0_25]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[?:1.8.0_25]
at net.minecraft.util.Util.func_181617_a(SourceFile:46) ~[h.class:?]
... 9 more
[11:26:18] [main/FATAL]: Error executing task
java.util.concurrent.ExecutionException: java.lang.NullPointerException
at java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[?:1.8.0_25]
at java.util.concurrent.FutureTask.get(FutureTask.java:192) ~[?:1.8.0_25]
at net.minecraft.util.Util.func_181617_a(SourceFile:47) [h.class:?]
at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:1086) [bib.class:?]
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:397) [bib.class:?]
at net.minecraft.client.main.Main.main(SourceFile:123) [Main.class:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_25]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_25]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_25]
at java.lang.reflect.Method.invoke(Method.java:483) ~[?:1.8.0_25]
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?]
at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
Caused by: java.lang.NullPointerException
at net.minecraft.client.network.NetHandlerPlayClient.func_147263_a(NetHandlerPlayClient.java:740) ~[brz.class:?]
at net.minecraft.network.play.server.SPacketChunkData.func_148833_a(SourceFile:96) ~[je.class:?]
at net.minecraft.network.play.server.SPacketChunkData.func_148833_a(SourceFile:18) ~[je.class:?]
at net.minecraft.network.PacketThreadUtil$1.run(SourceFile:13) ~[hv$1.class:?]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) ~[?:1.8.0_25]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[?:1.8.0_25]
at net.minecraft.util.Util.func_181617_a(SourceFile:46) ~[h.class:?]
... 9 more

Error bounces me out of game and back to server list, which is funny given I'm playing locally from a saved game. Happened after removing some ender chests and ender fluid tanks from EnderStorage-1.12-2.4.0.122-universal

Full log
latest.log

I fixed some stuff with packets in CCL 3.1.4 that may effect this, Please try with http://chickenbones.net/maven/codechicken/CodeChickenLib/1.12-3.1.4.316/ and see if that fixes the issue.

Thanks. Just pulled the file and will slot it for next game run. Appreciate the work in maintaining the mod. I'll report back if I run into the same issues.

I don't seem to be seeing anything similar in the log presently. Looks like it might be fixed. Thanks for the prompt replies and the dedication to the mod development.