http://pastebin.com/JCAx1d5j this is with Underground Biomes constructs
http://pastebin.com/GETLxDQb without UBC, issue happened when a block of congeiled slime fell into some liquid slime

http://pastebin.com/bpW1H1ds this was durring startup with another mod called Up Down and All Around

Uploaded v1.6.19 which should fix this issue. Thanks for reporting and helping me to find this nasty bug.

Not getting an EntityItem related crash with v1.6.19, looks like that bug is fixed.

To expand upon the second crash log involving my mod (Up And Down And All Around) and the crash log I found at https://minecraft.curseforge.com/projects/better-with-mods?page=6#c209

I would guess that you are modifying EntityItem such that subclasses of it no longer work properly.

In the linked crash log on curseforge, you can see the betterwithmods.entity.item.EntityItemBuoy.superSearchForOtherItemsNearby(EntityItemBuoy.java:57) stack frame before heading towards the native method java.lang.Class.getDeclaredMethods0 that throws the exception.

Furthermore, in the crash log with my mod included (http://pastebin.com/bpW1H1ds), you can see uk.co.mysterymayhem.gravitymod.CommonProxy.registerListeners(CommonProxy.java:63) before the native method goes and throws an exception.

On line 63 of my CommonProxy class, I'm registering EntityFloatingItem.class (an EntityItem subclass) to the event manager: https://github.com/Mysteryem/Up_And_Down_And_All_Around/blob/754c84642468d265b2963e32ec9adf4f9b227621/src/main/java/uk/co/mysterymayhem/gravitymod/CommonProxy.java#L63

If useful, the entire EntityFloatingItem class can be found at https://github.com/Mysteryem/Up_And_Down_And_All_Around/blob/754c84642468d265b2963e32ec9adf4f9b227621/src/main/java/uk/co/mysterymayhem/gravitymod/common/entities/EntityFloatingItem.java

Ok ... this crash is really weird, but i think i found the problem. Seems to be an issue by my name transformer. Could test if this file fixes all of the issues for you?

https://www.dropbox.com/s/om709id6vz8y2fa/CreativeCore%20v1.6.18%20mc1.10.2.jar?dl=1

Nice to hear that. Again thanks for helping out.

hurray for teamwork! Hopefully this also helps with the issues involving the crashes with UBC and Tinkers. IT seems like they're all somehow related one way or another. I'll go test it now, hopefully it solves those weird issues. I guess the other fix would be to simply remove Item Physics, as that seems to be the issue.

In the event that I still get the same crashes as the ones with Tinkers and UBC, I will come back and open up a new thread with any crashes I get. Thanks once again Creative and Mysteryem!