Lowers the Minecraft shield to make it less intrusive on your screen. Later there will also be an option to completely hide it in your off hand when not holding a weapon. (This mod only needs to be installed on the client)
The 1.9.4 version also works on 1.10
You can change the modes in the config file.
0 = Like vanilla Minecraft (changes nothing)
1 = lower the shield when held
2 = lower the shield when held en while blocking
3 = Completely hide the shield