Maps Only Update On Main Hand

Holding 2 Maps Of Different Levels At Once Causes The Map Only In Main Hand To Update...

That's All...
The Steps And All That...

Ps:Try Copy This And Run It On Command Block Then Get Hit By Zombies...
So Fun...
/give @p minecraft:shield 1 12 {Unbreakable:1,ench:[{id:0,lvl:30},{id:1,lvl:30},{id:4,lvl:30},{id:7,lvl:30},{id:19,lvl:3},{id:16,lvl:4}],HideFlags:127,display:{Name:"Reflective Shield",Lore:[Reflection III]}}