Affects Version/s: Minecraft 14w30c
Fix Version/s: None
Environment:Windows 7, Java 1.8
Entities move at normal speeds and minecraft performs fine in a superflat world with just a level of barrier blocks.
Everything in that barrier superflat world moves at a slower pace, making it frustrating to play. Entities even fall at very slow rates.
1. Create a superflat world with the gen set as 3;minecraft:barrier;1;
2. Spawn slimes and observe as they slowly jump around.
Here is a video proving this bug: