The following command is used to force the player to equip armor:
/replaceitem entity @p[type=Player] slot.armor.head chainmail_helmet 1 0 {display:{Name:"Archer Helmet",Lore:["You feel somewhat faster, and resistant to ranged damage"]},AttributeModifiers:[{AttributeName:"generic.movementSpeed",Name:"generic.movementSpeed",Amount:0.10,Operation:0,UUIDMost:24682,UUIDLeast:195471},,{AttributeName:"generic.armor",Name:"armor",Slot:"head",Amount:2.0,Operation:0,UUIDMost:100,UUIDLeast:100}],ench:[{id:0,lvl:2},{id:4,lvl:2}],Unbreakable:1}
And when run in a command block, it works 100% fine, but when it is part of the chain, it gives the output saying:
[14:09:34] Replaced slot slot.armor.head with 1 * [Archer Helmet]
However no changes were made to the player's GUI. Any ideas why this would happen? I'm playing Minecraft 1.10
Best Answer
First make sure the chain command block is set to "always active" and in a straight line with the other leading command block. Also the chain has to start with a regular command block then the chain of chain command blocks.